Walaa Said Selim

Effect of Two Sources of Microbial Phytase on Some Productive Performance, Meat Quality and Utilization Protein and Energy In Sasso Chicken diets By Walaa Said Selim B.Sc., Animal and Poultry Produc on (2003), Faculty of Agriculture (Damanhour), Alexandria University A. thesis Submitted to the graduate School of the Faculty of Agriculture (Damanhour), Alexandria University In Partial Fulfillment of the Requirements for the Degree of
1 Master of Science In Poultry Production Alexandria University August 2007 Advisor's Committee Prof. Dr. Abd El.Razek E.Tag El‐Din Professor of Animal Nutrition, Vice – Dean for Education and Student Affairs, Faculty of Agriculture (Damanhour), Alexandria University. Prof. Dr. Youssef Abd El‐Wahab Attia Professor of Poultry Nutrition, Head of Animal and Poultry
2 Production Department, Faculty of Agriculture (Damanhour), Alexandria University.
3 ACKNOWLEDGEMENT I would like acknowledge Prof. Dr. Abd El.Razek E.Tag El‐Din, Professor of Animal Nutrition, Vice – Dean for Education and Student Affairs, Faculty of Agriculture (Damanhour), Alexandria University, for their support, patience, helpful advice and revising the manuscripts. I wish to express my great thanks to Prof. Dr. Youssef A. Attia, Professor of Poultry Nutrition, Head of Animal and Poultry Production Department, Faculty of Agriculture (Damanhour), Alexandria University for his servicing as my major advisor. I was very please to have him as my advisor. I appreciate his idea for suggesting and planning of the work, support, guidance, statistical analyses and interpretation of the data and reading and correcting the manuscripts and all his patience as I was learning. I wish to express my great thanks to Dr. E M. A. Qota, Senior Researcher of Poultry Nutrition, Animal Production Research Institute, ARC, Ministry of Agriculture and Land Reclamation fir his support and help during the laboratory work. Also, I would like to thank the faculty, graduate students, and staff for their love, support and friendship. I wish to thank every single one for their love, support and much needed prayers I wish to thank my family members for their support of my work. I am eternally grateful for their love and encouragement for which no words can describe.
4 ‫ﺘﺄﺜﻴﺭ ﻤﺼﺩﺭﻴﻥ ﻤﻥ ﺍﻟﻔﻴﺘﻴﺯ ﺍﻟﻤﻴﻜﺭﻭﺒﻲ ﻋﻠﻰ ﺒﻌﺽ ﺍﻟﺼﻔﺎﺕ ﺍﻹﻨﺘﺎﺠﻴﺔ‬
‫ﻭ ﺠﻭﺩﺓ ﺍﻟﻠﺤﻡ ﻭ ﺍﻻﺴﺘﻔﺎﺩﺓ ﻤﻥ ﺍﻟﺒﺭﻭﺘﻴﻥ ﻭ ﺍﻟﻁﺎﻗﺔ ﻓﻲ ﻋﻼﺌﻕ‬
‫ﺩﺠﺎﺝ ﺍﻟﺴﺎﺴﻭ‬
‫ﺭﺴﺎﻟﺔ ﻋﻠﻤﻴﺔ ﻤﻘﺩﻤﺔ ﺇﻟﻲ‬
‫ﺇﺩﺍﺭﺓ ﺍﻟﺩﺭﺍﺴﺎﺕ ﺍﻟﻌﻠﻴﺎ ﺒﻜﻠﻴﺔ ﺍﻟﺯﺭﺍﻋﺔ ﺒﺩﻤﻨﻬﻭﺭ – ﺠﺎﻤﻌﺔ ﺍﻹﺴﻜﻨﺩﺭﻴﺔ‬
‫ﺍﺴﺘﻴﻔﺎﺀ ﻟﻠﺩﺭﺍﺴﺎﺕ ﺍﻟﻤﻘﺭﺭﺓ ﻟﻠﺤﺼﻭل ﻋﻠﻲ ﺩﺭﺠﺔ‬
‫ﺍﻟﻤﺎﺠﺴﺘﻴﺭ ﻓﻲ ﺍﻟﻌﻠﻭﻡ ﺍﻟﺯﺭﺍﻋﻴﺔ‬
‫ﻓﻲ ﺇﻨﺘﺎﺝ ﺍﻟﺩﻭﺍﺠﻥ‬
‫‪ ‬ﻤﻥ‬
‫‪ ‬‬
‫ﺒﻜﺎﻟﻭﺭﻴﻭﺱ ﺍﻟﻌﻠﻭﻡ ﺍﻟﺯﺭﺍﻋﻴﺔ )ﺸﻌﺒﺔ ﻋﺎﻤﺔ (‬
‫ﻜﻠﻴﺔ ﺍﻟﺯﺭﺍﻋﺔ ﺒﺩﻤﻨﻬﻭﺭ – ﺠﺎﻤﻌﺔ‬
‫‪ ‬ﺃﻏﺴﻁﺱ‬
‫ﺍﻹﺴﻜﻨﺩﺭﻴﺔ ‪2003 ) ‬‬
‫‪2007‬‬
‫‪5 ‬‬
‫(‬
‫‪ ‬ﻟﺠﻨﺔ ﺍﻹﺸﺭﺍﻑ‬
‫‪ -1 ‬ﺍﻷﺴﺘﺎﺫ ﺍﻟﺩﻜﺘﻭﺭ ‪ /‬ﻋﺒﺩ ﺍﻟﺭﺍﺯﻕ ﺍﻟﺴﻌﻴﺩ ﺘﺎﺝ ﺍﻟﺩﻴﻥ‬
‫ﺃﺴﺘﺎﺫ ﺘﻐﺫﻴﺔ ﺍﻟﺤﻴﻭﺍﻥ – ﻭﻜﻴل ﺍﻟﻜﻠﻴﺔ ﻟﺸﺌﻭﻥ ﺍﻟﺘﻌﻠﻴﻡ ﻭﺍﻟﻁﻼﺏ‬
‫‪ -‬ﻜﻠﻴﺔ ﺍﻟﺯﺭﺍﻋﺔ ﺒﺩﻤﻨﻬﻭﺭ – ﺠﺎﻤﻌﺔ ﺍﻹﺴﻜﻨﺩﺭﻴﺔ ‪. ‬‬
‫‪ -2 ‬ﺍﻷﺴﺘﺎﺫ ﺍﻟﺩﻜﺘﻭﺭ ‪ /‬ﻴﻭﺴﻑ ﻋﺒﺩ ﺍﻟﻭﻫﺎﺏ ﻋﻁﻴﺔ‬
‫ﺃﺴﺘﺎﺫ ﺘﻐﺫﻴﺔ ﺍﻟﺩﻭﺍﺠﻥ – ﺭﺌﻴﺱ ﻗﺴﻡ ﺍﻹﻨﺘﺎﺝ ﺍﻟﺤﻴﻭﺍﻨﻲ ﻭﺍﻟﺩﺍﺠﻨﻲ‬
‫‪ -‬ﻜﻠﻴﺔ ﺍﻟﺯﺭﺍﻋﺔ ﺒﺩﻤﻨﻬﻭﺭ – ﺠﺎﻤﻌﺔ ﺍﻹﺴﻜﻨﺩﺭﻴﺔ ‪.‬‬
‫‪6 ‬‬
1. INTRODUCTION Worldwide, protein and energy nutrition represented a major challenge to poultry production especially in the region where feedstuffs are imported. One of the possible approaches to reduce the feed cost for poultry is the use of low crude protein (CP) and low metabolizable energy (ME) corn‐soybean meal diet. Low‐CP and ME corn‐soybean diet can be improved by several technical methods, e.g. amino acids and/or enzymes supplementation. This especially important after the restriction set on the use of render feeds, environmental pollution and the need to least cost diet formulation (Attia et al., 2001; 2004; 2006 a,b). The use of low‐CP and ME diet was linked with decreasing Body weight gain ( BWG) and impaired feed conversion ratio(FCR) and this depends on chicks' age and magnitude of protein and ME restrictions (Attia et al., 2001). In the literature, the nutrient requirements of new improved local strains of chicks are scare (Shaldem, 2003; Khalifah, 2001; and A a et al., 2004). Sasso chicks are meat type chicks that widely used for meat production in Egypt, and have better genetic potential than native and new developed strains, but had lower genetic potential than broiler chicks. However, their nutrient requirements are scare and needs more efforts. The non‐mineral effect of phytase has been reported in the literature (Sebastian et al., 1998; Kies et al., 2001; Hatten et al., 2001; Selle et al., 2006a, b, c, Choct, 2006). These authors reviewed the effect of phytate molecule on the utilization of CP and ME and its inhibitory effects on proteolytic and energetic enzymes such as pepsin, trypsin and a‐amylase. These authors concluded that phytase improved CP and ME utilization of chicken diets. However, direct evidences about the effect of phytase on CP and ME availabilities in poultry diets are still limited and contradictory (Attia et al. 2001; 2004; Abd El‐Samee, 2002; Abou El‐Wafa et al., 2005). They reported that phytase had positive impacts on CP, amino acids (AAs) and ME availabilities for broiler diets. Kornegay et al. (1998) reported that phytase supplementation to a low‐AME wheat based diet for broilers improved AME utilization by 5.3% and ileal nitrogen diges bility by 3.2% (Ravindran, 1999a) as well as the utilization of N, P, Ca and Zn (Zanini and Sazzad, 1999). On the others hand, Boling‐Frankenbach et al.,( 2001); Peter and Baker,(2001); Augspurger and Baker (2004) reported that phytase did not affect CP and ME utilization in chicken diets. In addition, the effect of different types of phytase on productive performance and the utilization of protein and ME are scare and contradictory (Valaja et al., 2001; Camden et al., 2001; Augspurger et al., 2003; Roberson et al., 2005; Angel et al., 2006 a,b). This work aims to compare the effect of two sources of microbial phytase on productive performance, meat quality and utilization of low dietary CP and ME by Sasso chicks as a mean of reducing their feeding costs and their responses to low CP and ME diet.
7 2‐ REVIEW OF LITERATURE 2.1 Effect of dietary protein and energy levels: 2.1.1 Growth performance and digestibility of nutrients: Protein is the most expensive item in poultry diet and will remains due to limited supply of protein sources, and thus improving protein utilization will be considered a positive prospective in the view of both environmental and economical benefits. Attia (1986) found that 20 % CP from 0 to 8 wk of age followed by a 12% CP from 8 to 12 wk of age and a 15% CP up to 20 wk of age resulted in smaller SCWL at 20 wk of age with less total feed intake than the birds fed on 18, 15,12 % CP, respectively. Dietary CP 13, 15 and 17% had no appreciable differences in mortality rate of White Leghorn pullets. He reported also that energy level had no significant effect on growth performance of SCWL chicks, while increased feed consumption and improved feed conversion ratio (FCR) ratio. Attia (1986) found that increasing the dietary protein level from 13 to 17 % CP in the diet of SCWL pullets increased digestibility of protein, while decreased digestibility of ME. On the other hand, decreasing ME level improved the digestibility of CP by 3% and ME by ~2.5%. The same author reported that CP, ME level had no effect on mortality rate of SCWL. However, EL­Sakkaf (1995) fed four local strain Mandrah, Gimmizah, Alexandria and Silver Montazah diets containing 20, 18 and 16% protein from one­d of age and found that diet containing 20% protein, resulted in a greater body weight (BW) than those fed 18 and 16% protein. Thus, decreasing dietary protein resulted in a highly significant decrease in BW at 12 wk of age. Bunchasak et al. (1996) fed female broiler chicks low‐CP diet (17% CP, 3017 kcal ME/kg) for fied with a mixture of methionine + cys ne (1.1:1.0 w/w) at 0.64, 0.93 and 1.5%, meanwhile a diet containing 23% CP and 3017 kcal ME/kg served as a posi ve control. They found that body weight gain (BWG) of the broilers fed the diet with 17% CP diet supplemented with 1.5% methionine + cystine was similar to that of those on the control diet. The FCR was better (P<0.05) in control group than for low‐CP amino acid supplemented‐diet (P<0.05). One year la er, Bunchasak et al. (1997) fed female broiler chicks low‐CP diet (17% CP 3200 ME kcal/kg) supplemented with methionine + cys ne (1.1:1.0 w/w at 0.75, 0.94, 1.25 and 1.3 or 1.5%), while a diet with 21% CP and 3200 kcal ME/ kg served as the control from 3 to 6 wk of age. They found that BWG of chickens fed low‐CP diets supplemented with methionine + cystine was higher than those of the control chickens, while FCR and feed intake were not significantly different among various treatment groups. On the other hand, Hussein et al. (1996) indicated that BW at five and 12 wk of age was higher for SCWL pullets given 19% CP than for pullets given 16% CP, thus BW was significantly increased with each increase in protein level and feed intake was significantly increased through out the 18 wk growing period. However, increasing the level of protein 13.8, 15.8 and 18.9% during 2‐6 wk of age significantly increased feed intake up to 14 wk of age. Also, El‐Sherbiny et al. (1997) showed that broiler chicks fed low‐CP diets (20/18 or 18/16% CP in the starting/growing period) supplemented with lysine and methionine could perform equivalently to those fed the conven onal higher protein diet (22/20% CP) indica ng that methionine and lysine supplementation improved protein utilization.
8 Aggoor et al. (1997) investigated the effect of three levels of CP 18, 15 and 12% within each there were three levels of dietary energy (3400, 3200 and 3000 kcal/kg feed) on performance of Lohman broilers from 6 to 9 wk of age. They reported that BWG were significantly larger and FCR was better of broilers fed 15% CP supplemented with methionine and lysine than those fed 12 or 18% CP. Along the same line, Ferguson et al. (1998) suggested that if essential amino acids (EAAs) requirements are met, dietary CP could be decreased by nearly two percentages before production is adversely affected. In this regard, Attia et al. (1998) found that BWG was larger and FCR was better significantly with increasing level of CP and ME in the growing and finishing diets, and this correlated with increased feed intake of broiler chicks. Abdallah (1998) fed Golden Montazah male chicks' diets containing 22, 20, 18, 17, 16, 15, and 14% CP from hatch to 12 wk of age and reported that decreasing protein level from 20 to 16 % CP and sulfur amino acid from 0.72 to 0.67 % significantly decreased body weight, while feed intake was not significantly affected by dietary protein level. Abou EL­Wafa (1998) fed Golden Montazah male chicks diets containing 22% CP level in the starter diet from 1 to 28 d of age in the growing period from 28 to 56 d of age, CP level were 20 and 18%, meanwhile in the finishing period from 56 to 84 d of age, CP were 18 and 16%. He found that live BW at 8 and 12 wk of age was significantly heavier in the grower and finisher periods of birds fed diet containing 20/18% CP than those fed on low­protein 18/16% CP. Hussain (1999) found that Fayoumi, Gimmizah and Golden Montazah birds fed the higher protein diet 21.61% had significantly higher BW at 12 wk of age than those fed lower protein diet 15.34%. In addition, Rosebrough et al. (1999) found that broilers fed the diets containing 124g CP/kg gained less and converted feed less efficiently than birds fed diets containing 190g CP/kg diet. Peter et al. (2000) reported that protein level of 18, 16, and 24% CP improved weight gain and gain: feed impaired linearly (p< 0.05) as function of protein intake. Neto et al. (2000) reported that feeding the 17 vs. 27% CP diet decreased 21‐d BWG by 20% and increased FCR by 13%. In addition, Abou El‐Wafa et al. (2001) concluded that performance of broiler chicks fed 23/20% CP diet was similar to those fed 20/17% CP diet supplemented with adequate methionine and lysine to meet NRC (1994) recommenda ons. Moreover, EL‐Sayed et al. (2001) showed that Gimmizah, Mandara and Silver Montazah chicks fed high CP diet ( 20 or 19 %) with 2800 to 3000 kcal ME/ kg diet had significantly higher BW at 8 and 12 wk of age than those fed low CP ration (19, 16, 15 %) with different energy levels. They also revealed that the feed efficiency for Silver Montazah, Mandarah and Gimmizah chicks fed 18% CP was significantly (p ≤ 0.05) be er than those fed 15% diet during 0‐12 wk of age. However, Khalifah (2001) found that no significant differences among protein levels at 6 wk of age, in BW of Gimmizah and Golden Montazah chicks fed diets containing 18, 16 and 14% protein level. However, decreasing dietary protein levels from 18 to 16 % CP during 6‐12 wk of age significantly decreased body weight. However, no significantly difference was obtained when CP level increased from 14 to 16% CP, meanwhile feed intake of Gimmizah and Golden Montazah chicks was not significantly affected by dietary protein level. However, Attia et al. (2001) found that decreasing dietary CP significantly decreased growth, imapried FCR of broiler chicks, and further decrease of energy significantly decreased growth performance. Abd EL–Samee (2002) showed that feeding broiler chicks diets containing medium level of CP 20 or 18 % significantly increased body weight, and improved FCR
9 compared to those fed low level of CP 18 and 16% during the growing and finishing periods, respectively. Bregendahl et al. (2002) found that male broiler chicks fed low‐CP diets (19 to 20%CP) grew slower, used feed less efficiently, and retained less CP and more EE than chicks fed the control diets (P<0.05) despite increased dietary level of crystalline essential amino acids and nonessential amino acids in the low‐CP diets. Meanwhile, N excretion increased linearly (P<0.001) with N intake. Rahman et al (2002) compared four different treatments containing 23, 21, 19, and 17% CP, respec vely. Body weights varied significantly (P<0.01) at 8 wk of age were 1396.03, 1270.26 and 1175.95 g. FCR also improved (P<0.01) at the end of the experimental period which were 2.34, 2.44, 2.67 and 2.89 for 23, 21, 19 and 17% CP, respectively. Similarly, El‐Medany and El‐Afif (2002) found that decreasing CP level from 23 to 19.5% significantly decreased growth, feed intake and impaired FCR of broiler chicks at 21, and 42 d of age. Sklan and Plavnik (2002) found that increasing CP level for Cobb chicks from one to four wk of age resulted in linear decrease in feed intake while BWG and FCR changed quadratically with a smaller positive effect at the highest CP intake. Using constant EAAs: CP ratio at increasing CP intakes resulted in feed intake, BWG and FCR all increasing before reaching a plateau. El‐Husseiny et al. (2002) revealed that BW of birds fed 3000 kcal ME/kg were significantly higher than those fed 2800 or 3200 kcal ME/Kg diet. Decreasing ME level significantly increased feed consumption, digestibility of CP, and decreased digestibility of EE, ME, while increasing ME level improved significantly feed and protein conversion. Energy conversion for the high ME level was higher than the medium and low ME level. Yonemochi et al. (2003) found that broiler chicks fed low‐CP diet had similar growth performance, feed intake, FCR and mortality to those fed high‐ CP diet from zero to 21 and 22 to 49 d of age, while N excre on was decreased by 9%. In addition, El‐Husseiny et al. (2004) reported that feeding low CP diets (19%CP) supplemented with methionine and lysine to the amount recommended by NRC (1994) gave similar performance to that of high‐ CP diets (23%CP). Also, Abdallah et al. (2005) found that BWG of broiler chicks fed low‐CP diets (20 or 18%CP) from 0 to 3 wk and 18 or 16% CP from 4 to 7 wk of age supplemented with methionine, lysine and threonine was not significantly different from those fed of the 23/20% CP‐control diet. There was no significant difference in FCR of chicks fed low‐CP diet and that of the 23%CP‐control diet. Shaldam (2003) studied three CP levels as high levels of 22­20­18% CP in starter, medium of 20­18­16 %CP in growing period and low of 18­16­14 % CP in finishing period for Golden Montazah and Gimmizah chicks. Results indicated that the optima CP level for Golden Montazah males was 22, 20 and 18% in the starter, grower and finisher diets; while the crosspondings levels for Gimmizah strain was 20, 18 and 16% CP. Data indicated that increasing CP level significantly increased feed and CP consumption, while improved feed conversion. On the other hand, the opposite trend was shown in CP conversion. He reported that low CP level improved protein utilization by 19.5 and 12.6 % as compared to the high and the intermediate CP levels. He added that no significant differences in digestibility of crude fiber, ether extract and ash among different dietary CP
10 levels,were observed. Ozek (2004) found that different levels of ME (2600, 2700, 2800, 2900, 3000, 3100, 3200 kcal) did not significantly affect body weight. For the 0 to 8 wk period, significantly less feed was consumed by the partridges fed with 3200 kcal ME/kg diet than that for the partridges fed 2600, 2700, 2800, 2900 and 3000 kcal ME/kg diets. In the same period, the FCR of the partridges fed with 3200 kcal ME/kg diet was lower than did the partridges fed with 2600, 2700, 2800 or 2900 kcal ME/kg diets. He concluded that ME levels from 2700 to 2800 kcal ME/kg might be used in partridge starter diets. Attia et al. (2004) found that feeding roaster chickens resulted from meeting Sasso males and Golden Montazah females on 20% CP in the growing diet and 18% CP in the finishing diet, resulted in higher growth than chicks fed diets containing 18% CP in the growing diet and 16% CP in the finishing diets. They added that FCR was better on 20% CP level than 18% CP level and dietary CP level did not affect mortality rate of local strain used for roaster production in Egypt. Rezaei et al. (2004) used levels of CP e.g. 20.84, 17.84% in the starter and 18.12, 16.12% in the grower period with 12.12 MJ AME/kg diet. Reducing dietary CP decreased weight gain in the starter, grower and total period by 6.0, 4.6 and 5.6% respectively (P<0.05). It also decreased feed consumption in the starter period (P<0.05), however, dietary CP had no significant effect on mortality rate. Abd EL‐Gawad et al (2004) reported that CP levels of 23 and 21%, 20 and 18%and 18.5 and 16.5 % in the starter, grower and finisher diets, respectively, considering recommended level of CP and low level of CP, respectively. The overall results showed that feeding broiler chicks on diets containing either the optima level of CP or tested feed additives recorded significantly (P < 0.05) higher body weight, BWG, feed intake, performance index, better FCR and CP utilization efficiency than using low level of CP or the control. Nguyen and Bunchasak (2005) reported that dietary ME contents of 3000 and 3200 ME kcal/kg did not alter the growth performance of the Betong chicks, and 19% CP and ME contents between 3000‐3200 ME kcal/kg can met or over requirements for growth performance. Feed intake BW, BWG, and FCR ra o were increased by 0.53, 1.5, 0.81 and 0.48 %, respec vely of turkey fed 20% CP with 3250 kcal/kg diet compared to those fed 19% CP with 3100 kcal/kg diet (EL‐Mallah et al., 2005). They added that turkey chicks received the high level of CP and ME significantly (p < 0.05) increased diges bility of CP, CF and EE percentage by 1.39, 60.7 and 15%, respectively compared to those on the low level of CP and ME diet. Along the same line, Faria Filho et al(2005) showed that the decrease in CP levels from seven to 21 d of age contributed to lower nitrogen excretion in broiler chickens, but impaired performance. On the other hand, Waldroup et al. (2005a;b) concluded that the response to amino acid supplementation to low CP‐diet depends on the magnitude of decrease in dietary protein level. However, Corzo et al. (2005a) showed that performance from 5 to 21 d of age of broilers fed corn‐soybean meal diet containing 18% CP supplemented with adequate essential and non essential amino acids was similar to the control diet containing 22% CP, while improved protein utilization and decreased nitrogen excretion by ~32%. This revealed the need for additional nonessential amino acid when CP level was decreased substan ally by 4% points. Corzo et al. (2005b) found that increasing amino acid concentration in broiler diets from one‐d old to 42 d of age did not affect growth and uniformity, while decreased feed intake and improved FCR.
11 Atakora et al. (2006) found that dietary CP reduction improved energy utilization, retained energy and net energy numerically by 7­8 %. In addition, Abou El­Wafa et at (2005) studied the effect of three different ME levels (2800, 3000 and 3200 kcal ME/kg diet) in broiler diets and reported that formulated diet based on recommended energy level (3200 kcal ME/kg) significantly increased BWG, digestion coefficients of EE and AME and abdominal fat percentage compared to other dietary energy levels. Holsheimer and Ruessin (1993) and Abou­El­Wafa et al. (2001) and Saleh et al. (2004) found similar results. Sterling et al. (2006) conducted two trials to determine if a 3‐way interaction among genotype, dietary lysine, and CP is an important influence on dietary responses. The genotypes were Ross 308 and Cobb in trial 1 and Ross 508 and Arbor Acres Classic in trial 2. Regression analysis showed differences (P < 0.05) due to genotype for BWG, feed intake, and FCR in trial 1, and BWG, carcass yield, breast fillet and tender yields, and abdominal fat pad percentage in trial 2. In both trials, Ross broilers had a greater response to supplemental lysine when 17% CP was fed, but less response to supplemental lysine when 23% CP was fed for both BWG and FCR (3‐way interaction). Three‐way interactions between dietary CP , lysine levels and genotype were observed for BWG (P < 0.01), feed intake (P < 0.01), and FCR (P < 0.02) in trial 1 and for feed intake (P < 0.06) and FCR (P < 0.03) in trial 2. The 3‐way interactions demonstrate that quantitative differences exist between genotypes in response to increasing dietary levels of CP and lysine.
Venäläinen et al. (2006) found that dietary ME of 2868 kcal /kg significantly increased growth of broilers, feed intake and improved FCR compared to 2629 kcal/kg. 2.1.2. Carcass characteris cs and meat quality: Nowadays, carcass quality is the major important and interest in poultry industry due to increasing consumer interest in lean birds, low fat, low­cholesterol foods and the production of product added values (Attia et al., 2001). Dietary protein/amino acids are major elements affecting carcass characteristics, and quality of meat such as abdominal fat content and breast meat yield are greatly influenced by their levels (Summers and Lesson, 1984; 1985; Leclereq, 1995). In this regard, Moran et al. (1992) and Leclercq (1995) reported that CP rather than single amino acid had a major impact on abdominal fat deposition, and increasing CP intake decreased abdominal fat deposition. However, Leclercq et al. (1994) indicated that low­CP methionine and lysine supplemented­diet as those of the control diets resulted in almost complete prevention of increased carcass fat deposition from the finishing period. On the other hand, Cable and Waldroup (1991) found that protein level had no significant effect on dressed carcass percentage of broiler chicks at 8 wk of age. Han et al. (1992) reported that body fat content decreased when 19% CP was supplemented with methionine, lysine, arginine, valine, and threonine and glutamic acid, thus, there was no significant difference from 23% CP diet from 1 to 21 d of age. DeSchepper and DeGroote (1995)
12 concluded that carcass protein of broiler chicks fed 23% CP and those fed 16.5% CP was equivalent when essential amino acid just met minimum requirements. El­Nagger et al. (1997) fed three levels of 18, 15, and 12% CP within each, there were three levels of ME 3400, 3200 and 3000 kcal/kg from 45 to 70­d of age and found that carcass protein increased while carcass fat decreased with increasing CP level in broiler diets. In addition, abdominal fat and total body fats increased with decreasing CP and increasing energy level. Attia et al. (1998) indicated that increasing CP levels and ME resulted in increasing abdominal fat deposition, but dietary CP and ME had insignificant affect on dressed carcass percentage of Avain­34 broiler chicks. Abou EL­Wafa (1998) showed that dressed carcass, giblets and total edible parts at 12 wk of age were not affected by different dietary protein level different in Golden Montazah male chick diets. Abdallah (1998) indicated that dressed carcass weight and giblets (heart, liver and gizzard) as a percentage of live weight of broiler chicks was not significantly affected by dietary protein. Percentage of dressed carcass ranged between 66.29 and 64.53%. However, Neto et al. (2000) reported that feeding 17 vs. 27% CP diet increased abdominal fat pad weight by 104%. Garcia et al. (2000) found that methionine supplementation to broiler chicks fed 17% CP decreased relative liver size and increased breast muscle protein and did not affect abdominal fat pad size of broiler chicks. Moreover, Aletor et al. (2001) observed that low‐CP amino acid supplemented‐diet did not affect relative weight of breast, thigh, liver, heart, pancreas, spleen, dry matter, total body protein, total body ash and protein/fat ratio. Meanwhile, increased (P<0.05) abdominal fat (%) and total body fat and this occurred with increasing energy and fat retention while retention of protein and ash were not changed by feeding low‐CP amino acid supplemented‐diet from 3 to 6 wk of age. Attia et al. (2001) observed that low CP‐ methionine and lysine‐supplemented‐diet did not significantly affect percentage of dressed carcass, front, and hand parts, gizzard and pancreas while, increased abdominal fat and decreased liver percentage. On the other hand, low‐CP diet decreased CP percentage of muscle, and increased muscle EE and DM. They also added that decreasing ME levels besides decreasing CP level had no significant effect on carcass yield, organs, and meat quality. In addition, Sklan and Plavnik (2002) fed male Cobb chicks from one to four wk of age diet with increasing CP level and revealed that abdominal fat and the efficiency of protein retention decreased with increasing dietary CP intake and the efficiency of protein retention was quadratic, decreasing at higher protein intakes. El‐Husseiny et al. (2002) showed that dressed percentage of birds fed 3000 kcal ME/kg were significantly higher than those fed 2800 or 3200 kcal ME/kg diet, while decreasing ME level significantly decreased abdominal fat. Abd EL‐Samee (2002) reported that average of dressed carcass and giblets percentages showed no significant effect of different levels of CP in the diet for Hubbard broiler chicks. Shaldam (2003) concluded that feeding high CP levels 22­20­18% resulted in significantly higher percentage dressed carcass, breast, thigh and liver, while most of the organs were not affected by CP level in the diets for new developed local strain. Along the same line, Yonemochi et al. (2003) and Abdallah et al. (2005) concluded that the significant increase in abdominal fat was associated with low‐CP diet (18/ 16%CP‐diet) in the finisher period from 4 to7 wk of age. It is well understand that amino acids rather than total
13 nitrogen are more important for meat quality. On the other hand, Attia et al. (2004) reported that carcass yield, and internal organs were not significantly affected by dietary CP level or inclusion of different protein sources. Similar trends were observed in physical characteristics and chemical composition of meat except for CP of meat that was decreased significantly with decreasing CP level. In this regard, Corzo et al. (2005b) showed that increasing amino acid concentration in broiler diets from one to 42 d of age did not affect carcass yield, breast meat and back half, while significantly decreased abdominal fat. Nguyen and Bunchasak (2005) studied the effect of dietary ME levels of 3200 and 3000 kcal/ kg fed ad libitum from one to 42 d of age. High energy (3200 ME kcal/kg) increased abdominal fat yield from 0.39% to 0.57% (P<0.05) and when protein levels in the diets at 19% CP and ME contents between 3000‐3200 kcal/kg were met or over requirements, carcass quality were not affected. Abou EL‐Wafa et al. (2005) reported that percentage of dressed carcass, and breast of broilers were not significantly affected by dietary energy levels, however, abdominal fat deposition was significantly increased due to feeding high energy level e.g. 3200 vs. 3000 and 2800 kcal ME/kg diet. Peter et al. (1997) found similar results. In addition, EL Medany and El‐ Afifi (2002) found that decreasing dietary CP level decreased carcass yield, giblets, and increased abdominal fat of 21 d old chick, however, at 42 d of age carcass yield, giblets, and abdominal fat were not significantly affected by dietary protein levels e.g. 19.5 and 22.9% in the starter diets after feeding standard grower diets during the growing period. They added that reducing CP level increased the retention of DM, N, and P, while the increase in Ca retention was not significant. In addition, reducing CP decreased tibia width, tibia breaking strength, and increased tibia weight, however, tibia length and tibia weight were not significantly affected at the end of the growing period. Rezaei et al. (2004) found that decreasing dietary CP (208.4, 178.4 in starter and 181.2, 161.2 g/kg in grower period) with 12.12 MJ AME/kg diet had no significant effect on breast meat yield, but increased abdominal fat percentage significantly (P<0.05). Faria Filho (2005) showed that the decrease in protein levels from seven to 21 d of age contributed to lower nitrogen excretion in broiler chickens, but impaired carcass characteristics. Attia et al. (2006b) indicated that high energy diet (2900 kcal ME/kg diet) yield significantly higher percentage of drawn carcass and lower proventriculus, than the low‐energy diet (2700 kcal ME/kg diet), and had no significant effect on the other organs. Feeding the high‐ energy level increased significantly percentage DM and fat, while decreased percentage CP compared to low‐energy diet. Because of the negative effect of increasing dietary energy level on percentage CP of meat, water‐holding capacity of meat was decreased significantly. Meanwhile, the increase in color intensity of meat with increasing energy level could be attributed to change in fat content and consequences the increase in the deposition of fat‐soluble pigmentations. However, energy level had no significant effect on meat tenderness and pH value of meat. Sterling et al. (2006) found that increasing dietary CP decreased abdominal fat pad percentage in both experiments. Venäläinen et al. (2006) found that dietary ME of 12.0 MJ/kg significantly increased tibia weight, length, width and weight compared to 11.0 MJ/kg diet. Whereas, tibia ash,
14 Ca, and P contents (g/kg) were greater of broilers given diets with lower ME, while tibia breaking strength was not affected by dietary ME level. 2.1.3 Plasma constituents: Blood plasma of chickens, like other vertebrates, contains variety of proteins grouped by fractional precipitation into albumins and globulins. The lipid fractions of the avian blood are complex mixture, which have been roughly classified as free fatty acids, natural fat, phospholipids, and cholesterol esters. The level of plasma lipids are probably affected by the physiological and nutrition states of the bird (Sturkie, 1990). Type of dietary carbohydrate contributes hyper‐ lipidemia, whereas low carbohydrate or starchy diets reduced blood lipid (El‐Husseiny et al., 2004). In this regard, A a (1986) reported that egg type pullets tended to increase serum total protein as the level of dietary CP and ME were increased, while the opposite trend was shown in serum total lipids. El‐Nagger et al. (1997) found that total serum proteins and cholesterol were significantly (P<0.05) affected by dietary CP and ME levels. Rosebrough et al. (1999) observed that lipogenesis and malic enzyme activity were decreased (P<0.05) in birds fed low‐CP diet when investigated the interrelationships between dietary fat and CP levels in the regulation of lipid metabolism in the broiler chicken. In addition, Attia et al. (2001) obtained that low‐CP methionine and lysine supplemented‐diet resulted in lower serum protein, higher plasma total lipids, triglycerides, and cholesterol. While, broilers fed low protein‐low energy diet exhibited significantly lower plasma total protein, but insignificantly higher total lipids and significantly higher triglycerides than the positive control group. However, Aletor et al. (2003) found that broilers fed the low‐CP diets had higher concentrations of triglycerides and cholesterol in the liver than broilers fed the high‐CP diet. Attia et al. (2003a; b) found that level of methionine or lysine did not significantly affect plasma total protein, total lipids, cholesterol and liver enzymes AST, and ALT of ducklings. In addition, Sadaka (2006) found similar results with El‐Salam local chicken strain. Attia et al. (2003c) reported that there were no significant differences in total plasma protein and its fractions when the isonitrogenous diets containing different protein sources were compared. Meanwhile, low‐CP level significantly decreased plasma total protein and its fractions. There were no significant differences in plasma total lipids and its fractions when the two isonitrogenous diets were fed, nor was there a difference when CP level was decreased. On the other hand, decreasing CP by 2% had no significant effect in plasma Ca and inorganic P when low‐ CP diet was compared to its counterpart group fed the high‐ CP level. El­Husseiny et al. (2002) reported that decreasing energy level significantly total lipids, total cholesterol, glucose. Similarly, Abou EL­Wafa et al. (2005) found that energy levels from 3200 to 28090 kcal/kg diet did not significantly affect plasma
15 concentrations of P, Ca, Zn and Mg and as well as tibia ash. Mineral retention e.g. P, Mg, Ca and Zn was not significant affected by energy concentration of the experimental diets. Corzo et al. (2005a) observed that total plasma protein was not affected by feeding low CP­diet supplemented with essential and nonessential amino acids, while plasma uric acid was substantially (P<0.05) decreased. Along the same line, Ismail et al. (2006) revealed that ME levels in Japanese quail diets had no significant effect on plasma total protein and liver enzyme ALT and AST, while plasma total lipids and cholesterol was increased significantly when high­ME diet was fed. 2.2 Effect of phytase on improving protein and energy u liza on: 2.2.1 Phytic acid content in feedstuffs and their intrinsic phytase activity : Phytic acid salts represented 60‐70% of total phosphorus in all feedstuffs used in poultry diets. Phtyic acid represented at 2.5‐4.0 g/kg phytate phosphorus in practical broiler diets. It has been considered as an anti‐nutritional component in cereals, seeds and beans (Ravindran et al., 1995, Kies et al., 2001 and Selle et al., 2006a; b). Research has traditionally focused on its structure (Figure 1) that gives it the ability to bind minerals, proteins and starch, and the resulting lower absorption of these elements. Data presented in Table (1) declared the phy c acid contents of feedstuffs and its intrinsic phytase activity as well as optima pH and temperature. On the other hand, recent research have shown that phytic acid has many health benefits for diabetes patients. It lowers blood glucose response by reducing the rate of starch digestion and slowing the gastric emptying. Phytic acid has antioxidant, anticancer, hypocholesterolemic and hypolipidemic effects. In animal studies, phytic acid showed a protective action in carcinogenesis. This action could be explained by its mineral chelating potential. Some studies suggest that phytic acid acts as anti­cancer agent by reversing the proliferative effects of carcinogens. It might reduce depressions, in the treatment of Parkinson's disease, Alzheimer's disease and multiple sclerosis, and may reduce inflammation (Greiner et al., 2000 and Vats and Banerjee, 2004). ZN ++ HO Starch OH O=P­ O O o Protein CH2 + O­P=O Ca ++
o O H H H O=P­O HO O=P­O O 16 O NH3 O H O­P= O O O O­P­OH H OH CH2OH O starch O
O Fig 1. Possible interac ons between nutrients with a phytate molecule (Erdman ,1979) . 2.2.2. Source of phytases: 2.2.2. 1 Microbial phytase: Phytases can be derived from a number of sources including plants, animals and microorganisms, however, phytase produced by bacteria had pH optimum in natural to alkaline range with low yield precluded their use as feed additive (Vats and Banerjee, 2004). The international union of Biochemistry and Molecular biology (IUBMB) in consultation with the IUPAC­IUB Joint Commission ON Biochemical Nomenclature (JCBN) listed two types of phytases: 1) EC 3.1.3.8 Recommended name: a 3­phytase; systematic name: myo­inositol hexakis phosphate ­3­ phosphohydrolase; hydrolyzes the ester bond at the third position of myo­inositol hexakis phosphate to D­myo­Ins­1,2,4,5,6­pentakinphosphate and orthophosphate. 2) EC 3.1.3.26 Recommended name: a 6­phytase hydrolyses; systematic name: myo­inositol hexakis phosphate ­6­ phosphohydrolase; the ester bond at the sixth position of myo­inositol hexakis phosphate to D­myo­Ins­1,2,3,4,5­pentakinphosphate and orthophosphate. 17 Subsequent ester bonds in the substrate were hydrolyzed at different rates (Wodzinski and Ullah, 1996). Table 1. Phytin content in some common feedstuffs used in dietary formulation for poultry and their intrinsic phytase activity Feedstuffs Phytate % Maize 1 % of total P Phytase activity, U/ kg Optimum 3 pH Temperature ºC. 0.17 73 24 4.8 55 corn 0.42 64 41 NR NR Fine defatted corn germ 0.78 and bran 1 65 56 NR NR Sorghum 1 0.17 66 24 NR NR Wheat 1 0.18 55 1193 5‐6 45‐50 Wheat bran 1 0.63 69 2957 NR NR 1500 NR NR Gross defatted germ and bran 1 Trticale 2 Barley 2 0.27 64 582 5‐6 45‐55 Oats 2 0.29 67 40 5.0 38 Rice polishing 1 1.13 72 134 NR NR Soybean 0.37 65 62 4.5‐5.0 55‐58 Canola meal 2 0.70 59 16 NR NR Sunflower meal 2 0.89 77 60 NR NR Peanut meal 2 0.48 80 3 NR NR Cottonseed meal 1 0.84 63 36 NR NR Palm oil meal 1 0.29 57 34 NR NR Coconut meal 1 0.24 56 37 NR NR Brewery grains 1 0.30 24 39 NR NR NR, not reported (Godoy et al., 2005 1 , Kornegay et al , 1996 2 ; Greiner and Konietzny, 2006 3 )
18 Mullaney and Ullah (2003) described three classes of phytases based on their structural differences and varied catalytic properties. These include members of histidine acid phosphatases (HAPs), ß­propeller phytase (BPP) and purple acid phosphatases (PAP). 1) Phytase A (Phy A) and phytase B is histidine acid phosphatases (HAPs) and produced by Aspergillus niger 3135. Phy A characterized with two pH optima (2.5 and 5.0) and was heavily glycosylated with a molecular weight of 85kDa, while monomer protein was unglycosylated of 48.5 kDa. The enzyme was found to remain stable for months in crude culture filtrate and showed inherent thermostability possessing optimum temperature of 58ºC with ten cysteine residues involved in forming five disulfide bridges (Vats and Banerjee, 2004). 2) Phytase B (Phy B) is initial acid phytase with pH optima of 2.5. The enzyme lack phytate degrading activity at pH 5.0, while at pH 2.5 it efficiently hydrolyses phytate with a turnover number of 628 s ­1 as compared to 348 s ­1 for phytase A. Besides that, phy B is more thermostable than Phy A. The Escherichia coli app A gene, encoding a 6­phytase with pH 2.5 optimum was cloned and expressed in Pichia pastoris (Vats and Banerjee, 2004). 3) Phytase C a non­ histidine acid phosphate active side: Table 2. Physicochemical and kinetic properties of the three commercial phytases Source M. Isoelectr Optimum Substrate Kcat Km ­1 weight ic point pH (Mm) Temp selectivity (S ) kDa ºC. E. coli 42 6.3­6.5 4.5 60 Specific 6209 0.13 S. Cerevisiae 120 ­ 2.0­2.5 55­60 ­ ­ ­ A. Ficuum (PhyA) 85 4.5 2.5, 5.5 58 Specific 348 0.027 A. Ficuum (PhyB) 68 4.0 2.5 63 Broad 628 0.103 A. niger SK­57 60 ­ 2.5, 5.5 50 Specific ­ 0.0187 A. niger ATCC­9142 84 ­ 5.0 65 Broad ­ 0.10 Peniophora lycii 72 3.61 4­4.5 50­55 Specific ­ ­ (phyA) Plants Broad Canola Seed ­ ­ 5.2 50 ­ ­ Soybean 60 5.5 4.5­4.8 55 Broad ­ 0.048 Lupine seed LP 11 57 ­ ­ 5.0 Broad 523 0.08 Lupine seed LP 12 57 ­ ­ 5.0 Broad 589 0.30 Lupine seed LP 2 57 ­ ­ 5.0 Broad 533 0.13 (Vats and Banerjee, 2004) There were several phytases reported in the literature that did not posses histidine acid phosphate active side and thus have different requirements for their catalytic action
19 such as Bacillus subtilis. The enzyme had maximal activity at 55 ºC, pH 7.0, required Ca +2 for activity and stability and showed no homology with the active site sequence of HAPs. Thus, designated as phy C having phytase activity. Other phytases belongs to that group which were isolated from Klebsiella terrigena, Schwanniomyces castellii, Arxula adeninivorans, phytase of soybean, Arabidopsis thaliana (Vats and Banerjee, 2004). Nowadays, there are four types of phytase available in the market, if not more: 1) Aspergillus niger commercially (Natuphos, Phytase­3), the recommended dose of use for Natuphos is 500 FTU in broiler and turkey diets and 300 FTU in laying hen diets. 2) Peniophora Lycii commercially (Ronozyme TM P, phytase­6), the recommended dose of use for Ronozyme is 750 FYT in broiler diets and 450 FYT in laying hen diets. 3) E. coli phytase commercially (phyzyme, phytase‐6), the recommended dose of use for phyzyme is 0.01% of the broiler and turkey feeds, and 0.006% of the laying hen feeds. 4) Finase from company AB Enzymes, Finland. 3‐Phytase, EC 3.1.3.8 (Enzyme N. 28) produced by ‐1 Trichoderma reesei (CBS 528.94), having a minimum ac vity of Solid form: 5 000 PPU g and Liquid form: 1 000 PPU g‐1. 2.2.2. Genetic engineered phytase: There are also genetically engineered phytase that were expressed in plants such as tobacco, alfalfa, Arabidopsis, subterranean clover, sesame, soybean meal, canola, potato, rice, wheat and sugar cane. This may decrease the needs of microbial phytase in near future and animals from monogastric and ruminants speices could utilize phytic phosphorus, other chelating minerals, starch and protein and amino acids complexes in phytic molecules better (Attia et al., 2003a,b; Greiner and Konietzny, 2006). The phytase source and tissue expressed in it are shown in Table (3). Table 3. Phytase expression in genetically engineered plants Host plant Phytase source Tissue Tobacco A. niger Leaf (secreted) Tobacco A. niger Leaf Tobacco A. niger Seed Tobacco A. niger Root (secreted) Tobacco B. subtilis Root (secreted) Tobacco B. subtilis Leaf Alfalfa A. niger Leaf Arabidopsis A. niger Root (secreted) Arabidopsis E. coli Root (secreted) Arabidopsis A. niger Seed Subterranean clover A. niger Root (secreted)
20 Sesame A. niger Canola A. niger Potato A. niger Potato Consensus Rice A. fumigatus Rice S. occidentalis Rice E. coli+ S. ruminatium Wheat A. niger Sugarcane E. coli (Greiner and Konietzny, 2006) Root (secreted) Seed Leaf Root (secreted) Seed Seed Seed Seed Callus 2.2.3 Transgenic animals: Transgenic animals that could utilize phytic acid better and needs less requirement of dietary inorganic phosphorus and limit phosphorus pollution from animal agriculture is another area of interest. In this regard, Golovan et al. (2001a) produced transgenic mice that expressed E. coli app A phytase gene in salivary gland and secreted biologically active 55 KDa, glycosylated protein in the saliva. Expression of salivary phytase leads to significant reduction of fecal phosphorus. Similar results were shown with transgenic pigs (Golovan et al., 2001b). Selection producers were also employed to improve phytate phosphorus utilization in two lines of chickens that have high and low phosphorus bioavailability of 45.7 and 23.6%, and their regulatory genes were under investigations (Aggrey et al., 2004) 2.2.4 Effect of phytase source on animal performance: In the literature, the studies addressed the effect of phytase source on animal performance are rare. Zhang et al. (2000) compared between the efficacy of genetically engineered microbial (Natuphos) and plant (phytaseed) phytase for enhancing the utilization of phytate P in corn­soybean meal­based diets fed to young broilers to evaluate the safety of phytaseed phytase. Three levels of each of the two sources of phytase were used. Addition of both sources of phytase resulted in similar increase (P<0.05) of BWG and feed intake and an improvement in FCR. Piva et al. (1994) studied the effect of two phytases differing in activity obtained from Aspergillus niger on performance, mineral retention and deposition of Ca and P in bone in 2 trials with Cobb broiler chickens. In trial one, seven groups of 42 chickens were given a control diet, diets with high­activity phytase at 500, 100 or 2000 U /kg or diets with low­activity phytase at 500, 1000 or 2000 U/kg for 55 d. In experimental diets, part of the maize meal and soybean meal was replaced with wheat middlings and the mineral P source, dicalcium phosphate, was removed. In trial 2, control, high activity phytase and low activity phytase diets were compared in a balance experiment with 18 chickens, mean live weight 2.3 kg. In trial 1, BW was 8.5% greater (P<0.01) for high activity phytase diets than with the control diet. There were no differences between control and experimental diets in Ca, Na, Zn, P, urea, total proteins, and globulin and aspartate aminotransferase in blood. Tibia weight was lower (P<0.05) with 500 U of high activity phytase or low activity phytase than with 2000 U of high activity phytase or low activity phytase diets (­8.1 and ­11%, respectively). Tibia length was 4.3% greater with 1000 and
21 2000 U of low activity phytase diets and 4.5% with 1000 and 2000 U of high activity phytase diets than with the control diet (P<0.05). Bone Mn was greater (P<0.03) with the 2000 U of low activity phytase diet and Zn with 500 U of low phytase and high activity phytase at 500 U and 2000 U of phytase diets than with the control diet. The balance trial (trial 2) indicated a greater retention of protein (P<0.01) and of minerals (P<0.01) with the1000 U of high activity phytase diet than with the control diet. Retention of Cu was greater with the 1000 U of low activity phytase diet than with the control (P<0.01) or 1000 U of high activity phytase diets. Valaja et al. (2001) found that 750 U /kg of either A. niger phytase (Finase FP 500) or Trichoderma reesei (Finase P 500) phytase were equally effec ve for improving u liza on of P, apparent ileal digestibility of phosphorus, and P and Ca retention in broiler chicks fed corn‐ soybean diet, and decreased P excretion compared to the negative control. Both sources of A. niger phytase and Trichoderma reesei phytase were equally potent for improving the digestibility of P in maize and soybean meal diet in pigs (Näsi et al., 1999). The effects of wheat bran phytase (plant phytase) or a commercially available phytase‐3 (Natuphos® 600) on growth performance and skeletal integrity of toms and forms of li er phosphorus using five wk‐old Hybrid Converter toms fed corn‐soybean meal based mash diets for 12 wk were tested by Roberson et al. (2005). They found that BW was higher when toms were fed the control diet throughout the study compared to all other treatments and was not affected by phytase source. Tibia fracture force and ash were decreased by the low phosphorus diet but was similar for both phytase sources compared to the control diet. Litter soluble phosphorus content was decreased due to phytase supplementations. Feeding wheat bran phytase yielded similar bird responses and litter soluble phosphorus as Natuphos® when fed to commercial toms. Wu et al. (2006) reported that the addition of Phyzyme (phytase ‐6) or Natuphos (phytase‐3) significantly increased egg production and egg mass of hens fed the P‐deficient diet (0.11% NPP) to levels that were similar to hens fed the control diet containing 0.38% NPP. Feed intake of hens fed the diets supplemented with Phyzyme or Natuphos was significantly less than that of hens fed the control diet containing 0.38% NPP. Phyzyme or Natuphos supplementa on in the diets containing 0.11% NPP had significantly reduced excreta P of the control diet (approximately 58 and 54%, respec vely) with no adverse effect on egg produc on and egg mass. There were no significant differences in feed intake, NPP intake, total P intake, egg production, egg weight, egg mass, feed conversion, egg specific gravity, mortality, BW, and excreta P between the diets supplemented with Natuphos‐phytase and the diets supplemented with Phyzyme. They concluded that Phyzyme (phytase‐6) had the same positive effects on performance of commercial Leghorns fed corn‐soy diets as Natuphos (phytase‐3). Augspurger et al. (2003) compared the efficient of three types of phytase fungal phytase‐ 3 (Natuphos), phytase‐6 (Ronozyme) and bacterial phytase‐6 (Phyzyme) in improving performance and phosphorus utilization of broiler chicks and pigs. They concluded that both fungal phytases had similar effect on phosphorus utilization and toe ash, however, bacterial phytase (E. coli) had much greater effect on performance and toe ash and Ca and phosphorus retention. Combining both sources of fungal phytase‐3 and phytase‐6 or phytase ‐3 with E. coli phytase reveal no synergism between both sources with different site of initiation of phytate
22 degradation. The results revealed an advantage of the E. coli phytase over the commercial fungal phytases in young chicks. Zimmermann et al. (2003) studied the additivity of cereal phytases from wheat and rye and fungal phytase­3 (Natuphos) on the coefficient of apparent phosphorus absorption in growing pigs when added to phytase­ inactivated cereal based diets for pigs. The authors found that the supplementation of phytase –inactivated based diets with combinations of fungal phytase and wheat phytases, fungal and rye phytases as well as with wheat and rye phytases increased coefficient of apparent P absorption by 0.179, 0.150 and 0.058 in the wheat­, rye­ and wheat­rye based diets, respectively. They concluded that different sources of phytases exhibit linear additivity in their response on apparent P absorption in growing pigs, indicating that pigs could utilize intrinsic phytase present in feed stuffs efficiently, however, both source from phytases plant and microbial organs differ considerable in their ability to improve the digestibility of dietary phosphorus. Augspurger and Baker (2004) conducted four trials to investigate the effect of high levels of three phytase enzymes on P and protein utilization in chicks. The three phytases were derived from Aspergillus (Fungal Phytase 1), Peniophora (Fungal Phytase 2), and E. coli. In Trial 1, supplementa on of inorganic P from KH[2]PO[4] (0 to 0.20%) resulted in a quadra c (P < 0.05) response in weight gain, gain: feed, and bia ash concentra on but a linear (P < 0.01) increase in bia ash weight. Tibia ash was higher (P < 0.01) for chicks fed E. coli phytase‐6 than for those fed fungal phytase 1 at 500, 1000, and 5000 FTU/kg, but did not differ between these two phytases at 10000 FTU/kg. In Trial 2, E. coli phytase supplementa on at 1000 FTU/kg maximized growth and bone responses, whereas addition of either of the two fungal phytases resulted in increasing responses up to 5000 and 10000 FTU/kg. Dietary addi on of fungal phytase 2 resulted in the poorest (P < 0.01) responses among the three phytases. Escherichia coli phytase supplementation at 10000 FTU/kg in trial 3 resulted in bia ash (milligrams) responses that were greater (P < 0.05) than those resulting from either 0.35% inorganic P supplementa on or 10000 FTU/kg of fungal phytase Aspergillus and Peniophora. Trial 4 showed that E. coli phytase supplementation at either 500 or 10000 FTU/ kg did not improve protein efficiency ra o of chicks fed low‐protein soybean meal or corn gluten meal diets that were first limiting in either methionine or lysine, respectively. These results demonstrate that high dietary levels of efficacious phytase enzymes can release most of the P from phytate, but they do not improve protein utilization. Angel et al. (2006b) found that survivability of the enzymes during pelleting averaged 61.8, 25.4, and 7.1% for the Quantum phytase and was 77.2, 67.1, and 57.7% for the Ronozyme phytase at 70, 80, or 90 °C, respectively. The greatest BW (P<0.01) was seen in broilers fed the 0.40% NPP diet (731.4 g), followed by those fed the unpelleted Quantum phytase 1000 diet (685.9 g). Broilers fed the pelleted Quantum 1000 and Ronozyme 500 diets had similar weight at 18 d (688.1 and 684.1 g, respectively). Tibia ash was greatest (P<0.01) in broilers fed the 0.40% NPP diet and the unpelleted Quantum phytase 1000 diet (51.12 and 50.04%), followed by those fed the Quantum 500 and Ronozyme 500 unpelleted diets (49.86 and 48.82%). Broilers fed the pelleted Ronozyme 500 and Quantum 1000 diets had similar tibia ash (47.91 and 47.53%). P retention was similar (P>0.05, 57.5 and 54.7%) for birds on the pelleted Ronozyme 500 and Quantum 500 diets and was lower (P<0.01) for birds fed the 0.40% NPP diet (47.9%). P solubility at the time excreta were voided was similar for the Quantum 500 and Ronozyme 500 fed
23 birds. The Ronozyme enzyme survived pelleting at a much higher rate, especially at the lower temperatures, than the Quantum enzyme. Apparent efficacy of the enzymes after pelleting was similar, while the Quantum enzyme had better efficacy than the Ronozyme enzyme if fed in unpelleted diets. Ghasemi et al. (2006) added fungal phytase­3 (Natuphos) and Saccharomyces cervisiae (Sc47) to broiler diets containing two levels of NPP e.g. 100 and 50% of the NRC (1994) recommended levels. They reported that phytase improved the utilization of phosphorus of the diet containing 50% of the NRC recommended NPP levels, improved the utilization of phytate P, Ca, thus increased toe ash, body weight, and feed conversion. However, the effect of phytase on BW and FCR was less pronounced in the NPP adequate diet. On the other hand, Saccharomyces cervisiae had a greater effect on NPP adequate diet. however, tibia ash and P retention were not significantly affected by Saccharomyces cervisiae, and the combination of phytase and Saccharomyces cervisiae had some beneficial effect in low NPP. Veum et al. (2006) observed that there were linear and quadratic increases (P < 0.001) in 28‐d growth performance including feed intake, live body weight and feed conversion, bone breaking strength and ash weight, and the apparent absorption (g/d and %) of P, Ca, and Mg (P 0.01 for quadra c) with increasing concentra ons of E. coli phytase. Pigs fed the low‐P diets containing 2500 or 12500 U/kg of E. coli phytase had greater (P 0.01 or P < 0.001, respec vely) values for growth performance, bone breaking strength and ash weight, and the apparent absorption (g/d and %) of P, Ca, and Mg than pigs fed the positive control diet. The addition of E. coli phytase did not increase the apparent percentage absorption of N, GE, DM, Zn, Fe, or Cu. There were no differences in the efficacy of the E. coli or P. lycii phytase at 500 U /kg of low‐P diet for any criterion measured. In conclusion, there were linear increases in growth performance, bone breaking strength and ash weight, and the a pparent absorption of P, Ca, and Mg with increasing addition of E. coli phytase up to 12500 /kg of diet. In addition, all of these criteria were greater for pigs fed the low‐P diets containing 2500 or 12500 U of E. coli phytase/kg than for pigs fed the positive control diet. The addi on of 500, 2500, or 12500 U of E. coli phytase/kg of low‐P diet reduced P excre on (g/d) in manure by 35, 42, and 61%, respec vely, compared with pigs fed the positive control diet. Pillai et al. (2006) noticed that BWG and tibia ash (mg/chick and %) responded linearly (P < 0.05) to inorganic P addi on, and each level of E. coli phytase released more P than either fungal phytases 1 or 2, whether based on bia ash weight (mg/chick) or percentage. Weight gain and tibia ash were reduced (P < 0.05) by P deficiency, but gain and tibia ash of chicks fed E. coli phytase (250, 500, or 1,000 phytase units/kg) did not differ (P > 0.05) from that of chicks fed the P‐ adequate diet. In addition, carcass yield of broilers fed E. coli phytase was not reduced (P > 0.05). E. coli phytase effectively supported weight gain, tibia ash, breast yield, and leg yield compared with birds fed the P‐adequate diet, but clavicle breakage during processing was increased in birds fed E. coli phytase. E. coli phytase again effectively supported weight gain, and no differences (P > 0.05; compared with the P‐adequate diet) were noted for clavicle ash, diameter, or breaking strength. No differences (P > 0.05) in bone breakage during processing were noted among treatments. These results indicate that the addition of E. coli phytase to P‐deficient broiler diets improves growth, bone, and carcass yield and is more effective at releasing phytate‐bound P than the other fungal phytase products that were tested.
24 2.2.5 Factors affecting phytase efficiency: In the literature, many factors could affect the efficacy of phytase for example, moisture, temperature, pH, and the Ca and P content of the feed (Heinzl, 1996). The optima moisture for liberating inorganic P from phytate begins to work after oral intake of feed in the crop or gullet due to an increase of moisture content, which is the first limiting factor for phytase activity in diets (Heinzl, 1996). An adequate moisture content of the substrate is particularly important for the influence of phytase on phytate hydrolysis in vitro. The author reported that the minimum water content must be ~ 20‐25% while the maximum ac vity was achieved at moisture of 30% (Heinzl, 1996). It is well recognized that enzymes are protein and are sensitive to moisture and temperature, while high temperature during pelleting, expanded, and extruded can results in denaturing of protein and loss of activity. The optima temperature was measured setting the rela ve ac vity at body temperature (37º C) at 100%. Meanwhile, maximum activity is reached ~ 60º C. thus pelle ng temperature should not exceed 60º C. Thereby, temperature affect the stability of phytase after pelleting, expanding, and extruding (Heinzl, 1996). Microbial phytase has different pH activities at 2.5 and at 5.5 pH depends on its type of bacterial or fungal, and this different from pH of plant phytase (4‐6; Table 1 and 2). Thus, microbial phytase has more activity in the crop, gizzard and proventriculus (Heinzl, 1996; Vats and Banerjee, 2004). Thus, protect it from the act of pancreatic proteases, which would decrease the activity of phytase. Calcium and phosphorus content of the experimental diets was also shown to affect the efficacy of phytase in gut. It is well know that Ca level interferes with phytase activity in the gut due to increasing pH value in the gut, and the optimum Ca level for phytase activity is <0.75% and at high pH there is formation of Ca phytate, which precipitates, thus can't be attacked by phytase (Lantzsch, 1989; Heinzl, 1996; El­Deeb et al., 2000). In addition, the Ca:P ratio as an increase in this ratio, has linearly decreased the effect of phytase on P retention (Qian et al., 1997; Lei and Stahl, 2000, Lou et al., 1999). In this regard, Schöner et al. (1993) concluded that fungal phytase was not adversely affected by increasing Ca levels, however, to obtain maximum breakdown of phytate it is recommended not to supplement Ca at rates higher than physiologically necessary. In virto studies, high phosphorus was found to repress the synthesis of acid phosphatases and phytases, while limiting phosphate conditions result in their expression (Vats and Banerjee, 2004). Han and Gallagher (1987) found that a sharp decline in phytase production by A. niger even at 0.05% phosphorus in the medium with absolute no production at 0.1% and the above, indicating the end product inhibition in phytase synthesis. For more details and excellent review, please see Vats and Banerjee (2004). 2.2.6 Effect of phytase on growth performance of birds:
25 Phytase supplementation improved BWG and feed intake (Simons et al., 1990; Sebastian et al., 1996a; Van der klis et al., 1996; Farrell and Martin, 1998; Waldroup et al., 2000; Desouky, 2001 and Salem et al., 2003). The improvements in growth of broiler fed a low phosphorus diet with phytase supplementation may be interpreted based on (a) an increase in absorbed phosphorus (Waldroup, 1999 and Desouky, 2001). (b) the release of other minerals from the phytate­ mineral complex (Sebastian et al., 1996a and El­Deeb et al., 2000), and (c) an increase in digestibility of protein and of amino acids and starch (Van der Klis and Versteegh, 1991 and Attia et al., 2001; 2003a,b). Similarly, supplementation of phytase to broiler diets improved FCR (Savlor et al., 1991; Edwards, 1993; Schoner et al., 1993; Desouky, 2001 and Lan et al., 2002). However, some studies indicated that, phytase supplementation had no significant effect on FCR in broiler chicks (Simons et al., 1990; Sebastian et al., 1996a; Mohamed et al., 2001 and Salem et al., 2003). Simons et al. (1990) showed that phytase addition to low phosphorus corn soybean meal diet for broiler chicks improved growth rate; and FCR of low phosphorus diet thus there were similar to or even better than that of the control diet. Sebastian et al. (1997) reported that microbial phytase‐3 increased BWG (P<0.01) and feed intake (P<0.004) at 19 d in male chickens; in females, phytase increased (P<0.012) only BWG at 19 d. Huff et al. (1998) indicated that phytase addition to low dicalcium phosphate corn‐soy bean meal diet in broiler chicks resulted in significant increase in body weight. Denbow et al. ( 1998) found that fungal phytase as Natuphos (Phytase‐3) improve growth performance of broilers fed low NPP diets from 7 to 21 d of age and increased BW, and feed intake and improved FCR. Wilson et al. (1999) observed that addition of phytase caused an increase in FCR of barley‐maize‐rapeseed meal‐soybean meal diet. On the other hand, Vetesi et al. (1998) showed that phytase aaddition to the feed at a lower inorganic P level did not cause changes in broilers BWG, but improved FCR by 5.6%. Similar results were reported by Zanini and Sazzad (1999) as phytase supplementation had no effect on broilers growth performance. However, Zhang et al. (1999) found that BWG of broilers fed the diet reformulated with fungal phytase‐3 did not differ from those fed the control diet, while FCR was not affected by phytase supplementation. Cabahug et al. (1999) revealed that increasing dietary phy c acid from 10.4 to 15.7 g/kg (from rice pollard) negatively influenced BWG, feed intake, FCR, and these adverse effects were partially overcomed by phytase‐3 addition at 400 and 800 FTU/kg diet. The improvements occurred in broilers BWG and FCR by phytase were greater in high‐phytic acid containing diets. Ravindran et al. (1999b) found that ME of wheat was increased by 5.3% with phytase, while BWG and FCR were improved with the combination of phytase and xylanase. Along the same line, Raw et al. (1999) found that phytase addi on at (250 and 500 FTU/kg) to broiler diets improved BWG and FCR. In addition, Sohail and Roland (1999) and Zyla et al. (2000) observed an improvement in BW, feed intake, and FCR with phytase . Waldroup et al. (2000) observed that phytase supplementation to low NPP containing diet maintained livability and improved BWG and FCR of broilers. Attia et al. (2001) noticed that fungal phytase‐3 added at 1000 FTU/kg diet improved AMEn and true amino acid availability of yellow corn, soy bean meal; and rice bran, while decreased N, EE, CF, and CA contents in excreta
26 and improved their digestibilities. The reduction in growth rate, FCR and economical efficiency occurred by decreasing dietary protein and energy levels was negated by fungal phytase ‐3 addi on at 700 FTU/kg diet for broilers. Along the same line, El­Deeb et al. (2000) observed that microbial phytase­3 (Natuphos) addition (0 , 500 and 1000 FTU/kg) in the broilers diet composed of corn and soybean meal contained rice bran at 15% from hatch to 42 d of age. They found that phytase supplementation significantly (p <0.01) increased BWG. However, phytase had no influence on feed intake and FCR. Yan et al. (2001) fed 3­wk old broiler chicks diets with NPP levels of 0.10, 0.15, 0.20, 0.25, 0.30, 0.35, 0.40 and 0.45% without or with fungal phytase­3 supplementation (800 FTU/kg diet). In the absence of phytase, NPP levels of 0.33, 0.186, and 0.163% were required to optimize BWG and FCR. While in the presence of 800 FTU/kg diet, NPP levels of 0.24, 0.151 and 0.109% were needed to optimize BWG and FCR. Demyr and Sekerolu (2002) observed that the low P­Ca+phytase diet significantly (P<0.05) increased BWG by 8.4% and feed intake by 7.03%. Phytase at 1200 U/kg was added to the diets except the control. The ash in the excreta significantly (P<0.05) decreased with phytase supplementation and the P in excreta was decreased by 9.56 to 18.26% by adding phytase in diets containing 0.45 and 0.30% NPP. Abd El‐Samee (2002) reported that when broiler chicks fed diets containing medium level of CP with adding fungal phytase‐3 (750 FTU/kg), the average value of broiler performance were improved significantly compared with the control group. In addition, phytase supplementation improved digestibility coefficient of organic matter (OM), CP, ether extracts (EE) and nitrogen free extract (NFE). El‐Medany; and El‐Afif (2002) showed that fungal phytase‐3 addi on at 750 FTU/kg to broiler diets containing different levels of NPP (0.30; and 0.45) and CP (19.5; 23%) they concluded that increased BWG by 11% of low CP diet. Moreover, adding phytase to normal CP level (23%) increased BWG by 4% compared with unsupplemented groups, feed intake was increased and FCR was improved by 8 and 3%; and 3 and 0.6% by adding phytase to 19.5 and 23% CP respectively. Balasubramanian et al. (2002) noticed that the supplementation of the different levels of fungal phytase­3 at 500,750 and 1000 FTU/kg to low 0.3%NPP diets significantly (P<0.01) increased BWG and feed intake (P<0.05) and improved FCR. Aksakal and Bilal (2002) revealed that addition of phytase significantly, (p < 0.05) increase BWG, feed intake, and improved FCR of broiler chicks. Viveros et al. (2002) found that phytase supplementation significantly (p<0.05) improved BW (at 3 and 6 wks of age) and increased feed consumption (p<0.0122) only at 3 wks. However, FCR was not affected at any age by addition of phytase. Performance of chicks fed supplemental phytase with 0.35% (0 to 3 wk) and 0.27% (3 to 6 wks) NPP was comparable to those fed the control diet. However, Qota et al. (2002) reported that phytase addition at 500 FTU/kg to broiler diets contained 10% linseed cake did not influence on weight gain, feed intake, and FCR. Shirley and Edward (2003) observed that broiler chicks fed a basal corn­soybean meal diet (from 0 to 16 d old) that contained an analyzed 22.2% CP, 0.88% Ca, a deficient total P (tP) level of 0.46% (phytate P = 0.272%), in addition to a positive control diet [ 0.70% tP ]. The dietary fungal phytase­3 (Natuphos) levels evaluated were 0, 93.75, 187.5, 350,750, 1500, 3000, 6000. in addition, 12000 FTU/kg of diet. They found that supplementing phytase from 0 to 12000 significantly increased BWG, Feed intake, and
27 improved FCR. Ribeiro et al. (2003) studied the interactions between dietary NPP levels (0.16 and 0.24%), and phytase supplementation (280 FTU/kg diet) on performance of broilers fed maize­soybean­based diets up to 12 d of age. They found that addition of phytase significantly (p<0.01) improved BWG, increased feed intake and improved FCR. Along the same line, Selle et al.(2003) showed that phytase addition plus xylanase [xylan endo­ 1,3­ beta ­xylosidase] in wheat­based poultry diets increased (p<0.05) BWG (7.3%) and improved FCR (7.0%) of broilers (7­28 d post­hatch). Salem et al. (2003) found that phytase addi on at 600 FTU/kg to broiler diets containing different levels of P, increased BWG and feed intake of the low P diet compared with the normal P diet (control). In addition, phytase supplementation had no significant effect on FCR . Wu et al. (2003) found that phytase addition improved BW irrespective of diet type or NPP level at 3.0 or 4.5 g/kg, but the magnitude of improvements in the P‐deficient wheat‐soy diet was greater than maize‐soy diet. Abd El‐Hakim and Abd El‐Samme (2004) found that phytase addi on at 750 FTU/kg to broiler diets from 7‐42 d of age during summer season, improved body weight; BWG; FCR and performance index. Abdo (2004) studied the effect of phytase addi on levels e.g. 0.0; 500; and 1000 FTU/Kg to broiler diets contained 0, 25 and 50% level of Nigella sativa seed meal to substitute soybean meal protein and concluded that phytase addition at 500 or 1000 FTU/kg to 25% Nigella sa va seed meal diet resulted in the best BWG compared to the control group. Hassanabadi et al. (2004) found that phytase addi on to 0, 250, 500, 750 and 1000 FTU phytase/kg diet improved live BW, feed intake, FCR. Simialry, Aggoor et al. (2004) found that phytase addition at 600 FTU/kg diet containing rapeseed meal increased BWG and improved FCR and digestibility of CP and CF. Also, Attia et al. (2004) found that phytase addi on at 600 FTU/Kg diet for hybrid chicks resulted of meeting Sasso × Golden Montazah improved growth and FCR. On the other hand, El‐Nagmy et al. (2004) investigated the effect of 3 levels of phytase (0, 400, 800 FTU/kg) to broiler diets containing two levels of protein (23/21% and 20/18% CP) during the growing/finishing period, respectively and concluded that phytase supplementation improved BWG and FCR. Wu et al. (2004) studied the effect of phytase at 0 and 500 FTU/kg diet and xylanase at 0 and 1000 unit/kg diet individually or in combination to broilers wheat‐soy diets. They found that supplemental phytase improved the BWG and FCR by 17.5 and 2.9% respec vely. The corresponding improvement due to addition of xylanase was 16.5 and 4.9% respec vely, the combination of phytase and xylanase caused no further improvements in broiler performance. In addition, Cufadar and Bah yarca (2004) reported that fungal phytase‐3 supplementa on at different levels significantly improved growth, feed intake and improved FCR. Cheng et al. (2004) reported that BWG was significantly (P<0.01) increased and no significant differences were recorded in FCR among dietary treatments when broilers fed basal diet (0.4 % NPP ) supplemented with phytase from 7 to 28 d of age. In addition, Onyango et al. (2005) found that Escherichia coli phytase (phytase‐6) addi on at 500 or 1000 units/kg of diet increased BWG (P< 0.05), feed intake (P< 0.01), retention of P; Ca; and N: and amino acids. Abou El‐Wafa et al. (2005) reported that phytase addi on at 750 FTU/kg feed containing different level
28 of NPP. They concluded that phytase supplementation to low NPP diet improved growth performance and economic efficiency. El‐Ghamry et al. (2005) studied the effect of phytase at 500 FTU/kg without or with 1g/kg multienyzme mixture to broiler diet containing 20/30 % rice polishing during the growing/ finishing period. Results indicated that phytase without or with multienzyme mixture increased BWG and improved FCR significantly compared to their negative control with the combination of phytase and multienzymes yield better results than phytase alone. Afsharmanesh and Pourreza (2005) found that in the low Ca diet, fungal phytase ‐6 (Ronozyme) Ghazalah et al (2006a) studied the effect of two sources of phosphorus ,(di‐ calcium phoshate being inorganic and one mealas organic source), two levels of AP (0.35 and 0.25 %) and three levels of microbial phytase (500,750 and 1000FTU /Kg) .The addi on of microbial phytase at either 750 or 1000FTU /Kggave the best values of the studied parameters. However, supplemented the diet with 1000FTU /Kg phytase restore the performance to level of the control. alone significantly increased BWG and feed intake. Pillai et al. (2006) observed that Escherichia coli phytase addition at 250, 500, and 1000 U/kg increased BWG, compared with birds fed the P‐adequate diet. Veum et al (2006) studied the interactions between dietary NPP level 0.15% and Escherichia coli phytase‐6 supplementation at 0, 100, 500, 2500 and 12500 units phytase/ kg diet or Peniophora lycii phytase‐6 supplementation at 500 units phytase/ kg diet. Pigs fed the low –P diets plus Escherichia coli phytase addi on 2500 or 12500 U /kg of diet increasing values for growth performance. Selle et al. (2006c) found that bacterial phytase‐6 (Phyzyme XP) supplementa on at 0,500,750 FTU /kg increased BWG (P< 0.01), mortality rates over 42 d, feed intake (P< 0.001) in the grower and finisher phases and improved FCR (P< 0.02) in starter and grower phases. Ghazalah et al (2006b) studied the effect of using different levels of protein (high , HCP; medium ,MCP and low, LCP ) along with diferent levels of phytase (0.0,500,750,1000FTU /Kg ) in broiler diet on their growth performace, nutrient digestibilitiy and economic effcieny. Supplementing diet with phytase at levels up to 100 FTU /Kg improved all growth performance . Pirgozliev et al. (2007) found that phytase increased feed intake by 11.2 and 6.5%, BWG by 10.2 and 13.2% and improved FCR by 0 and 7.6% for chickens and turkeys, respec vely. The authors concluded that both species can tolerate phytase concentra ons much higher than 1000 U of phytase and these concentrations have further beneficial effects compared with lower phytase concentrations. This work supports the hypothesis that supplementing turkey diets with phytase will need to be considered independently of chicken diets, considering the components in the diets, such that optimal responses can be obtained.
29 2.2.7 Effect of phytase on protein/amino acid utilization: Protein­phytate complexes may be present in plant feedstuffs (Prattley and Stanley, 1982). The interaction between phytic acid and proteins is believed to be of an ionic type and depends on pH (De Rahm and Jost, 1979). At low pH, phytic acid forms electrostatic linkages with the basic amino acids (arginine, histidine and lysine), resulting in insoluble complexes. As the pH approaches the isoelectric point, the charge on the proteins neutralizes and, the phytate is no longer bound and become soluble. In this soluble state, phytate complexes with protein because of the presence of the divalent cations. These cations, usually Ca, Mg, Zn, act as a bridge between negatively charged carboxyl groups and the phytate. The earliest reports indicated that phytase has a positive effect on protein availability in poultry (Van der Klies and Versteegh, 1991). Similar results were observed by Farrell et al. (1992), El­Medany and El­Afifi (2002) and Abd El­Samee (2002) with broiler chicks. Their results indicated that amino acid availabilities were improved, with addition of phytase (1000 FTU/kg). More evidences (Kies, 1997, Martin et al., 1998; Ravindran et al., 1999a; Attia et al. 2001; Attia, 2003a;b, Rutherfured et at.,2004 and Cowieson et al., 2006a) indicated that phytase improved CP/ amino acids utilization of broiler and ducklings diets and the improvements were within the range from 4 to 6% and depends on the type of dietary feedstuffs. Yi et al. (1996b) indicated that phytase addi on at 750 FTU/kg feed to corn‐ soybean meal diets increased N and ileal amino acid digestibility and improved growth performance of Turkey pullets. They also observed that adding microbial phytase increased dietary phytate phosphorous diges bility at 0.45% NPP with 25.5 or 28% CP and at 0.60 NPP with 22.5% CP diets, which is consistent with the idea that phytase increased nitrogen and amino acids ileal digestibility resulted from hydrolysis of phytate phosphorous. Moreover, when dietary phosphorus and CP requirements of turkey poults were met, added phytase did not influence the digestibility of P, N or amino acids. Furthermore, Rutherford et al. (1997) in vivo study showed that free lysine from a complex with phy c acid ~ 20% was bound and half of this was liberated upon addition of phytase. Sebastian et al. (1997) revealed that microbial phytase increased apparent ileal digestibility and apparent "faecal" digestibility of most of the amino acid (AA), particularly in female chickens. Namkung and Leeson (1999) found that phytase‐ supplemented diet had higher diges bili es for nonessen al amino acids (P<less or =>0.05) and total amino acids (P<less or =>0.01) than controls. Alone the same line, Ravindran et al. (1999a) reported that phytase increased ileal digestibilites of amino acids of soybean meal; cottonseed meal; canola meal; sunflower meal; wheat middlings; and rice polishing. Again, the magnitude of response varied among feedstuffs and among different amino acids within a feedstuffs which could indicate that different phytate contents. Moreover, Um and Paik (1999) observed that phytase addition to corn‐soy bean meal diet for laying hens improved retention of nitrogen significantly. Ravindran et al. (2000) indicated that supplemental phytase increased ileal digestibility of arginine, histidine, iso‐leucine, leucine, lysine, phenylalanine threonine, and valine. There were no differences in the phytase responses between 400 and 800 FTU phytase / kg diet. Phytase had positive impacts on protein and amino acid availabilities of broiler diets (Biehl and Baker, 1997; Sebas an et al.,
30 1998; A a et al., 2001; Abou El‐wafa, 2005). Others, Kornegay et al. (1998) evaluated the addition of phytase to a two protein, amino acid diet on performance, ileal amino acid digestibility and carcass measurements of broilers, they showed that addi on of phytase at 300 or 400 FTU/kg restored the reduced performance, breast meat yield and improved digestibility of amino acid. In addition, Camden et al. (2001) found that supplemental phytase improved ileal digestibility of nitrogen and amino acids (alanine, arginine, aspartic acid, glycine, isolecuine, leucine, lysine, methionine, threonine, tyrosine, and valine) of P­deficient diets linearly with increasing level of phytase supplementation, with no differences between the two types of phytase products phytase­3 and 6. Pourreza and Classen (2002) reported that phytase addition at 0, 500 and 1000 FTU/kg improved protein digestibility significantly. Attia et al. (2001) indicated that amino acid availabilities were improved as a results of fungal phytase‐3 supplementa on at 1000 FTU/kg. The magnitude of improvement being the highest (13.7%) in corn followed by decrease order of rice polishing (5.6%) and soybean meal (2.8%), respec vely and individual amino acids responded differently within and among feed ingredients. Pourreza and Classen (2002) reported that fungal phytase‐3 addition at 500 and 1000 FTU/kg improved BWG, feed consumption, FCR and bone ash significantly (P<0.05). Difference between enzyme levels at 500 and 1000 FTU/kg was not significant regarding BWG, feed consumption, FCR and bone ash. Overall, addition of phytase to the diets containing wheat caused an improvement in performance and FCR when birds were fed a lower protein diet supplemented with 800 FTU phytase /kg diet compared with the other group fed 23/20% crude protein. Lan et al. (2002) revealed that phytase addition to low diet significantly improved CP digestibility. Abd El‐Samee (2002) found that using either higher level of sulphur amino acids or fungal phytase significantly (P<0.05) improved the average values of broiler performance, except for feed intake. Also, growth performance parameters were improved when chicks fed diets containing medium level of CP (21 %) with adding phytase compared with the control diet (23% CP). A a (2003a) noticed that phytase addi on at 600 FTU/kg to duckling diets containing different levels of lysine improved performance of diets containing the lowest level of lysine, thereby there was no significant difference from the positive control which containing the highest level of the added Lysine. A a (2003b) indicated that phytase addi on at 600 FTU/kg to duckling diets containing different levels of methionine, improved true digestibility of lysine, methionine; and cys ne by 1.3; 1.0; and 5.8% respec vely. In addition, Yonemochi et al. (2003) found that phytase‐3 (A. niger) addition to broiler chicks fed low‐CP diet had no significant effect on growth, feed intake, FCR and mortality, while decreased DM, N and phosphorus excre on by 19.2, 14.4 and 19.3%, respectively. Along the same line, El‐Nagmy et al. (2004) observed supplementing broiler diets with phytase either at a level of 400 or 800 FTU/kg diet significantly improved (P<0.05) the BWG during the experimental period (1‐7 wk) of the low protein. Phytase mediated an improvement in protein digestibility. Similarly, Selle et al. (2003) showed that phytase addition plus xylanase [xylan endo‐1,3‐ beta ‐xylosidase] in wheat‐based poultry diets increases amino acid digestibility with the combination exceeded the sum of the individual increases generated by phytase and xylanase for alanine, aspartic acid, glutamic acid, glycine, histidine, isoleucine, phenylalanine, threonine, tyrosine and valine.
31 Abd El­Hakim and Abd El­Samee (2004) investigated the effect of feed restriction program [skip a d, skip half a d, providing the actual requirements of protein and energy, and feeding ad libitum (control diet) without or with phytase supplementation (0 and 750 FTU /kg diet) on broilers performance. They found that phytase supplementation significantly (P<0.01) improved BWG and FCR and increased feed intake at starter and finisher periods. Aggoor et al. (2004) found that fungal phytase­3 significantly increased BWG by 20.1 % and insignificantly improved FCR by 1.2% compared to SBM­ control group and insignificantly increased BWG by 7.9% compared to the RSM control group. Similar findings were reported by Attia et al. (2004) with sesame meal, indicating the phytase improved the utilization of low quality protein supplements rich in phytic acid. Jubarah and Davis (2006) found similar results with rapeseed meal when phytase supplementation at 0.4% kg diet yielded the highest retention of nitrogen. Attia et at. (2003c) found that phytase addition to low protein diet and normal protein diets containing untraditional protein sources improved protein utilization of local hybrid chicks. Hassanabadi et al. (2004) found that phytase addi on to 0, 250, 500, 750 and 1000 FTU phytase/kg of diet for Ross broiler chicks improved protein efficiency ratio. Microbial phytase had a significant effect (P<0.05) on the apparent diges bility of amino acids and protein. Adding 250 and 500 FTU of phytase/kg of diet significantly increased the diges bility of all amino acids (except alanine) and protein. Higher levels of phytase caused poor diges bility compared to 250 and 500 FTU. Similarly, El‐Nagmy et al. (2004) observed that phytase addi on to 0, 400 and 800 FTU/kg diet and 2 levels of CP (23/21% and 20/18%) during the growing and the finishing periods, respec vely significantly improved (P<0.05) protein u liza on efficiency during the experimental period (1‐7 wk). Phytase induced improvement in protein utilization when birds were fed a lower protein diet and supplemented with phytase at 800 FTU/kg diet compared with the other group fed 23/20% crude protein. Supplementing broiler diets with microbial phytase at 800 FTU/kg diet significantly (P<0.05) increased nitrogen retention. Similarly, Cowieson et al. (2004 and 2006a) observed that supplementation of myo‐inositol hexaphosphate with phytase reduced the excretion of endogenous amino acids in broiler chickens; and increased amino acids digestibility. Along the same line, Rutherfurd et al. (2004) fed three low‐P corn‐soybean meal diets supplemented with 0, 500 or 750 FTU/kg of microbial phytase to 21 d old broiler chickens, and reported that fungal phytase‐3 improved true ileal amino acid digestibility. Afsharmanesh and Pourreza (2005) found that in the low Ca diet, fungal phytase ‐6 (Ronozyme) alone significantly increased BW and feed intake, protein and P digestibility compared to the negative and the positive control. In addition, Abou El‐Wafa et al. (2005) indicated that crude protein digestibility and nitrogen balance were improved when phytase‐3 (natuphos) was added to low P‐diet. Onyango et al. (2005) showed that E. Coli phytase‐3 at 500 and 1000 U/kg was efficacious in improving BWG , feed intake, bone ash and retention of P, Ca, N and number of amino acids including arginine (quadratic response to level of phytase), histidine and valine (linear response to the level of phytase) threonine, tryptophan, asparater and praline. Meanwhile, phytase did not affect FCR and apparent digestibility of dry matter and energy. Selle et al. (2006c) showed found that phytase‐6 (Phyzyme XP) supplementa on at 0,500,750 FTU /kg increased digestibility of most
32 amino acids bing arginine (3.1%), his dine (3.4%), isoleucine (3.1), leucine (3.4%),lysine (3.7%), valine (3.9%), aspar c acid (6.1%),glutamic acid (3.3%), serine(3.2%) and tyrosine (3.5%).A total amino acid digestibility improved by5.3 %. Recent results by Atakora et al. (2006) revealed that phytase improved mineral and possibly amino acid digestibility. However, there was building body in the literature regarding the positive effect of phytase on protein/amino acid utilization as evidenced by the review by (Sebstain et al., 1998; Kies et al., 2001 and Selle et al., 2006a). Zhang et al. (1999) reported that the effect of fungal Natuphos phytase‐3 at 600 FTU/kg diet on apparent ileal digestibilities of CP and amino acids were not significant in P‐ inadequate diet. Peter et al. (2000) and Peter and Baker (2001) indicated that 1200 FTU fungal phytase‐3 (Natuphos)/kg diet did not increase either CP or amino acid utilization in corn gluten meal and in soybean for young chicks fed phosphorus adequate diet. Augspurger and Baker (2004) found that E. coli phytase at either 500 or 10.000 FTU/kg did not improve protein efficiency ratio of chicks fed low‐protein soybean meal or corn gluten meal diets that were first limiting in either methionine or lysine, respectively. Similarly with pigs, Veum et al. (2006) found that E. coli phytase ‐6 did not increase the apparent percentage absorption of nitrogen, GE, DM, Zn, Fe and Cu, and there were no differences between fungal phytase‐6 and E. coli phytase‐6 at 500 U/kg of low‐ phosphorus diet for any criterion measured. Along the same line, Akyurek et al. (2005) found that fungal phytase‐6 (Ronozyme) did not affect ileal protein digestibility of broiler chicks fed P‐in adequate diet. Similarly, Hammad et al. (2005) found that microbial phytase supplementa on at 0, 500, and 750 and 1000/kg diet did not significantly affect protein digestibility of broiler chicks fed phosphorus inadequate diet. Ghazalah et al (2006) studied the effect of using different levels of protein (high , HCP; medium ,MCP and low, LCP ) along with diferent levels of phytase (0.0,500,750,1000FTU /Kg ) in broiler diet on their growth performace, nutrient digestibilitiy and economic effcieny. Supplemen ng diet with phytase at levels up to 100 FTU /Kg improved all growth performance the group of chicks fed HCP +1000FTU /Kg diet revealed significantly the best values of and PI as well as better alues of CP, EE and OM digestibilitiy ,ME and NB compared to the control . Oduguwa et al. (2007) reported that phytase supplementation to malted sorghum sprouts containing 140 g tannin /kg and 99% of this was bound did not significantly affect the true nitrogen retention, apparent and true amino acid digestibility. This may explain its low amino acid digestibility and the lack of effect of the various treatments for poultry. Olukosi et al. (2007) reported that low ME and P levels in the negative control diet depressed BWG, FCR (P < 0.001), while phytase supplementation improved ileal digestible of N and P digestibility compared to the negative control. Ghazalah et al (2007) studied the effect of two levels of crude protein (18%, 16%), levels of methioinine (0.42%, 0.31%) and microbial phytase levels (0.0, 500 FTU/Kg on laying hen performace , egg shell thickness, nutrient digestibilitiy coefficiennts and economic ffcieny. The addition of microbial phytase at 500 FTU /Kg of lying hen diets significantly (P< 0.05 )
33 improved the aveage values of egg production , egg weight , feed conversion ratio , digiestibility coefficient of organic matter, crude protein and ether extract. 2.2.8 Effect of phytase on metabolizable energy (ME) utilization: Phytate reduces glucose absorption rates, which led to the suggestion that phytate may adversely affect starch digestion by interacting with starch directly, or proteins closely associated with starch granules or inhibition of a­ amylase activity (Thompson and Yoon, 1984 and Thompson, 1998). In addition, it has been postulated (Ravindran et al., 2000) that calcium phytate may increase the formation of metallic soaps in the gut lumen, with a corresponding reduction in the utilization of saturated fats. They reported that phytase improved AME, and the retention of dry matter in broiler chicks fed different levels of phytic acids, and no differences were shown between 400 and 800 FTU of fungal phytase­ 3(natuphos) kg diet. The improvement in energy as a result of addition of phytase in poultry diets (Sebastian et al., 1998; Ravindran et al., 1999a ; Kies. et al., 2001; Attia et al., 2001 and Attia, 2003a, b) may be attributed to liberation of Ca ions necessary for a­ amylase activity, which is involved in starch digestion, to the improvement of protein and amino acids utilization or the decrease in the utilization of saturated fat (Ravindran et al , 1999a). Thomson and Yoon (1984) reported that addition of phytic acid to wheat reduced starch diges bility by 60% compared with that of the control group. Years latter, direct evidences indicated that phytase improved energy availabilities for animals, which reflected in improved bird performance (Zanini and Sazzad, 1999; Ravindran et al., 2000; A a et al., 2001a; Camden et al., 2001; Arafat, 2002; A a, 2003b and Abou El‐Wafa, 2005). Also, Farrell et al. (1993); Farrell and Mar n (1998); Um and Paik (1999) and Ravindran et al. (1999a) revealed that phytase addition to chick or duck diets containing corn, cottonseed meal or soybean meal; wheat, or wheat bran, and rice bran improved ME value, within the range of 3‐4% (Ravindran et al., 1999a). Sebastian et al. (1998) reviewed the evidences about the effect of phytase on nutrient availability and reported that phytate decreased the α‐amylase activity by complexing with the calcium ions needs for enzyme activity. It is known that α‐amylase occurs in all plants, animals and microorganism, which requires calcium ion for its activity and to maximize its stability. Ravindran et al. (1999a) studied the influence of microbial phytase on AME of wheat­ sorghum­soybean meal diets containing three levels of phytic acid and two levels of NPP, and concluded that phytase improved AME by 6% of diets containing adequate levels of NPP. Simialry, Ravindran et al. (1999b) observed that the AME value of wheat was increased by 9.7% with xylanase and 5.3% with phytase, while the combination of both enzymes increased AME by 19% and similar trend was seen in terms of ileal amino acid digestibility values. Namkung and lesson . (1999) investigated the effect of phytase on the performance and amino acids in a 15‐d trial using 192 d‐old male broilers fed diets with or without phytase supplementation that were low in Ca (0.9% for control and 0.79% for phytase treatment) and NPP 0.45% NPP for control and 0.35% NPP for phytase treatment. The diet supplemented with phytase had a higher AMEn (P<less or =>0.01) than the control. Along the same line, Johnston
34 and Southern (2000) men oned that phytase supplementa on at 600 FTU/kg diet to corn‐ soybean meal diet increased ME by 45.7 kcal ME/kg of diet. Furthermore, Ravindran et al. (2001) reported that phytase supplementation, increased the AME and the response reached plateau at 750 FTU/kg diet. Kies et al. (2001) reviewed this topic to obtain equivalent energy value for phytase and calculated this value to be 72.9 kcal ME / kg diet due to addi on of 500 FTU/kg. In addition, Camden et al. (2001) found that supplemental phytases (finnfeed phytase, Bacullus subtilis fermentation) a 3‐phytase (EC 3.1.3.8), and Natuphos phytase‐6 (EC 3.1.3.26) Aspergillus ficuum gene that over expressed in Aspergillus niger improved ileal digestibility of starch and lipids and these improvements being reflected in enhancements in ileal digestible energy and AME of phosphorus deficient diets. They concluded that the increase in AME was linear with increasing level of phytase supplementation with no differences between the two type phytase products. Lan et al. (2002) found that phytase addition to low NPP diet significantly improved AME value and DM digestibility. Arafat (2002) and Attia et al. (2003) found similar results with the improvement within the range of 3 ‐ 5 %. Shirley and Edwards (2003) found that supplemen ng phytase from 0 to 12.000 FTU/kg significantly increased AMEn. Selle et al. (2003) showed that phytase addition plus xylanase [xylan endo‐1,3‐ beta ‐xylosidase] in wheat‐based poultry diets improved AME by 181 kcal/ DM. On the other hand, Biehl and Baker (1997) reported that phytase had no effect on TMEn in cecectomized roosters fed dehulled soybean meal. Along the same line, results with pigs. Shelton et al. (2003) indicated phytase addition had a small, mostly non‐significant effects on energy availability in phosphorus inadequate diets for growing pigs. Saleh et al. (2003) found that phytase had no significant effect on DM digestibility of maize and had no effect on the viscosity at both peptic and pancreatic phases, and did not affect CP digestibility, either. Wu et al. (2003) studied the effect of phytase at 500 FTU/kg to broiler diets containing two types of diets (maize‐ soy or wheat‐soy) and two level of NPP (3.0; or 4.5 g/kg). They found that phytase addition improved AME values of wheat‐based diets but had little effect on the AME of maize based diets as shown by a diet type with phytase interaction. The AME was not influenced by dietary NPP. On the other hand, El‐ Nagmy et al. (2004) inves gated the effect of 3 level of phytase 0, 400, 800 FTU/kg to broiler diets containing two level of protein (23/21% and 20/18% CP) during the growing / finishing period respectively and concluded that phytase supplementation improved digestibility coefficients of organic matter, crude protein, ether extract, and nitrogen free extract due to microbial phytase addition. Wu et al. (2004) studied the effect of phytase at 500 FTU / kg diet; and xylanase at 1000 unit/kg diet) individually or in combination in broilers fed wheat‐soy diets. They concluded that phytase or xylanase supplementation alone resulted in numerical improvements in AME but the differences were not significant. The combination of the two enzymes significantly increased AME Moreover, Onyango et al. (2005) found that E. Coli phytase at 500 and 1000 U/kg did not affect apparent digestibility of dry matter and energy. Similarly, Veum et al. (2006) with pigs found that E. coli phytase ‐6 did not increase the apparent percentage absorp on of GE and DM, and there were no differences between fungal phytase‐6 and E. coli phytase‐6 at 500 U/kg of low‐ phosphorus diet for any criterion measured. On the other hand, Hammad et al. (2005) found that
35 microbial phytase supplementa on at 0, 500, 750 and 1000/kg diet similarly improved significantly ether extract digestibility of broiler chicks fed phosphorus inadequate diet. Selle et al. (2006c) found that phytase at 750 FTU/kg supplementation of modified diets significantly increased AME by 65 kcal /kg on a dry matter basis. Along the same line, Akyurek et al. (2005) found that fungal phytase‐6 (Ronozyme) did not affect ileal DM diges bility, however, increased ileal EE digestibility of broiler chicks fed phosphorus deficient diet. In addition, Abou El‐Wafa et al. (2005) found that EE, and AME were improved significantly when phytase‐3 (natuphos) was added to low NPP diet. However, Onyango et al. (2005) showed that E. Coli phytase‐3 at 500 and 1000 U/kg did not affect apparent diges bility of dry ma er and energy. Recently, Pirgozliev et al. (2007) found that phytase increased AME by 1.4 and 5.7%, and AME intake by 13.1 and 9.8% for chickens and turkeys, respec vely. The AME data were subjected to a species x phytase interaction, whereby increasing the phytase dosage led to significant increments in parameters for turkeys but not broilers; broilers recovered significantly more ME from the diet than did turkeys. A quadratic relationship existed between dietary AME and phytase concentrations. They concluded that both species can tolerate phytase concentrations much higher than 1000 phytase units and that these concentra ons have further beneficial effects compared with lower phytase concentrations. The work supports the hypothesis that supplementing turkey diets with phytase will need to be considered independently of chicken diets, considering the components in the diets, such that optimal responses can be obtained. Oduguwa et al. (2007) revealed that phytase supplementation to malted sorghum sprouts containing 140 g tannin /kg and 99% of this was bound did not significantly affect the true dry matter digestibility, total tract digestibility of AME and TME , indicating that the tannin content of malted sorghum sprouts is high and it appeared to be bound with other nutrients thereby reducing their availability. This may explain its low AME and the lack of effect of the various treatments for poultry. Olukosi et al. (2007) reported that phytase had no effect on ileal digestible energy. Ileal N and P diges bility was higher (P < 0.05) in the phytase supplemented diet compared to the negative control, however, the improvement in P retention due to phytase supplementation decreased by 50% as the chicks matured. The data also shows that the chicks benefited more from the enzyme addition at a younger age and that the contribution of the enzymes to nutrient retention decreased with age in chickens. 2.2.9 quality: Effect of phytase on carcass characteristics and meat Recently, quality of meat and carcass yield become in an important in poultry industry due to the further process and increasing consumers awareness of healthy products (Attia et al., 2001). Sebastian et al. (1995) pointed out that phytase supplementa on (600 units/kg) increased the ash percent in both head and shaft portions of dry, fat‐free bia bone of 21‐ d old broiler chicks to a level comparable to that of the normal P diet. Phytase supplementation increased the weight of total P and Ca in tibia‐head ash by 36.6 and 25.0%, respectively. Kornegay
36 et al. (1998) found that fungal phytase‐3 to the low phosphorus diet restored breast meat yield to the level of the positive control group. In addition, Cabahug et al. (1999) reported that bone ash content was increased with phytase addition at 400 and 800 FTU/ kg. Attia et al. (2001) recorded an improvement in carcass characteristics when fungal phytase‐3 was supplemented to a low protein‐low energy diet. Phytase had no effect on dressing carcasses percentages, breast and thigh meat yields and most of internal organs (Peter et al., 1997; Kornegay et al., 1998; A a et al., 2001). Sebastian et al. (1996b) reported that phytase supplementation of a low­P broiler diet significantly (P<0.04) increased the ash content of tibia but had no effect on minerals (P, Ca and Zn) content in the ash. The optimum level of ash content was observed with the 0.6% Ca diet plus phytase. Yi et al. (1996a) noted that phytase addition linearly increased ash percentage of dried toes. In another study, Yi et al. (1996b) found that ash percentage of toe and tibia were not affected by added Zn but were linearly improved by adding phytase, however, the amount of ash in toe or tibia was increased by Zn and phytase. The concentration and amount of Zn in toe and tibia were linearly increased by adding Zn and phytase. Moreover, Mitchell and Edwards (1996) suggested that bone ash and plasma phosphorus are the most sensitive and reliable methods for determining the animal’s phosphorus need. Along the same line, Qian et al., (1997) found that added phytase at the levels of 300, 600 and 900 FTU/kg of broiler diet linearly increased toe ash content. Similarly, Rowland et al. (1997) reported that percentage of bone ash is usually positively correlated with bone breaking strength. This may be due to the increased availability of phosphorus and Ca from phytate­mineral complex by the action of phytase. Denbow et al. (1998) found that fungal phytase as Natuphos (Phytase­3) improved toe ash weight of broilers fed low NPP diets from 7 to 21 d of age. Sohail and Roland (1999) men oned that phytase 300 FTU/kg had a much greater influence on bone mineral content, bone density, bone breaking strength and bone ash in broilers fed 0.225% available P than in broilers fed 0.325% NPP, showing greater effect of phytase at the low phosphorus level. Zanini and Sazzad (1999) found that microbial phytase supplementation at 500 FTU phytase /kg feed increased the concentrations of Ca and Zn in the tibia because of higher intakes of dry matter, N, P, Ca and Zn. Ravindran et al. (2000) observed that phosphorus retention was similarly improved due to 400 and 800 phytase supplementation with the effect was greater in low NPP diets. Yan et al. (2001) found that in the absence of phytase, NPP levels of 0.33, 0.186, and 0.163% were required to op mize bia ash. However, in the presence of 800 units of phytase / kg diet, NPP levels of 0.24, 0.151 and 0.109% were needed to op mize bia ash. This revealed that phytase improve bone mineralization and decreased its requirements for NPP. Camden et al. (2001) found that addi on of 500 U of phytase/kg diet significantly increased toe ash with no significant differences between the two sources of phytase‐3 and‐6. Attia et al. (2001) found that phytase supplementa on at 700 FTU/Kg diet improved dressing of broiler chicks fed low protein low‐energy diet. They also found that phytase supplementa on at 700 FTU/Kg with or without 0.075% Op zyme, had no effect on chemical composition of meat and liver, as well as physical characteristics of meat, which correlated significantly with dietary protein and energy concentration. Also the same line, Abd El‐Samee (2002) reported that phytase addi on at 750 FTU/kg to broiler diets contained different crude
37 protein and TSAA, did not significantly affect on carcass characteristics and meat analysis of 7 wk of age broiler chicks. Qota et al. (2002) found that phytase addi on at 500 FTU/kg to broiler diets contained 10% linseed cake did not significantly affect dressing, liver, gizzard, heart, giblets, and pancreas percentages, as well as meat physical characteristics such as pH value; tenderness; WHC; and color intensity. phytase increased percentage CP of meat, while decreased fat and DM content of meat. Viveros et al. (2002) found that phytase supplementation at 500 FTU/kg diet supplementation to phosphorus deficient diet increased tibia weight, tibia ash, and Mg and Zn, concentration and reduced the relative liver weight. In addition, AbdEl­Samee (2002) reported that no significant differences in both carcass characteristics and meat analysis values were detected due to phytase supplementation in broiler diets with either different levels of CP or sulphur amino acids. Moreover, El­Medany and El­Afifi (2002) found that either phytase, CP or NPP did not significantly affect yield of meat. However, Scheideler and Ferket (2000) reported that phytase supplementation had no effect on total carcass yield. Lan et al. (2002) found that phytase supplementation increased tibia ash to those fed normal NPP level. Tibia Ca was increased, while tibia Mn and Cu were decreased, and tibia Zn and P were not significantly affected by phytase supplementation. Along the same line, Attia (2003 a,b) found that phytase supplementation at 600 FTU/kg to duckling diets containing different levels of lysine or methionine, did not affect carcass yield, chemical composition, and physical characteristics of meat. Salem et al. (2003) found that phytase addition at 600 FTU/kg to broiler diets containing different levels of phosphorous had no effect on carcass yield at 4 wk of age, however it increased carcass yield at 7 wk of age. Yonemochi et al. (2003) found that supplementation of 500 U of A. niger phytase/kg diet for broiler chick's decreased significantly abdominal fat deposition compared to the negative control fed P­ inadequate diet. Augspurger et al. (2003) found that either supplementation of phytase ­3 or phytase­6 to phosphorus inadequate diet significantly increased bone mineralization, however, P­release value were 0.081, for Natuphos phytase, 0.043% for Rononzyme, and 0.108% for E. coli phytase. Shirley and Edwards (2003) reported that supplementing phytase from 0 to 12.000 FTU/kg diet significantly increased tibia ash and tibia ash weight. Abd El­Hakium and Abd El­Samee (2004) found that phytase supplementation o at 750 FTU/kg to broiler diets from 7­42 d of age during summer season had no effect on carcass characteristics. Abdo (2004) concluded that phytase had no significant effect on carcass characteristics values 6 wk old broiler chicks. El­Nagmy et al. (2004) found that phytase addition at 400 and 800 FTU/kg to broiler diets containing different levels of plant protein, did not affect carcass yield of 7 wk of age. Cheng et al. (2004) observed that adding phytase to a corn­soybean diet containing 0.41% NPP fed to broilers from 7 to 28 d of age significantly (P<0.01) increased tibia ash weight and minerals content (Ca and P) above those fed the control diet. Adel­Hakim and Abd El­Samee (2004) found that phytase supplementation significantly (P<0.05) increased dressed carcass percentage and abdominal fat of broilers compared with those fed the control diet without phytase supplementation. Cufadar and Bah yarca (2004) reported that Natuphos phytase‐3 supplementa on to low phosphorus diet increased carcass yield, neck, back+ breast and wings, while did not affect toe ash. However, Onyango et al. (2005) found that Escherichia coli phytase (phytase‐6) addition at
38 500 or 1000 units/kg of diet increased percentage bia ash (P < 0.01) and reten on of P and Ca. Moreover, Afsharmanesh and Pourreza (2005) found that in the low Ca diet, fungal phytase ‐6 (Ronozyme) alone significantly increased tibia ash, and P digestibility compared to the negative and the positive control. However, Akyurek et al. (2005) found that supplemental fungal phytase‐6 (Ronozyme) did not have any effect on toe ash content, although, significantly improved phosphorus and calcium availability. Veum et al (2006) studied the interactions between dietary NPP levels 0.15% and Escherichia coli phytase‐6 supplementa on at 0,100,500,2500,and 12500 units phytase/ kg diet or Peniophora lycii phytase‐6 supplementa on at 500 units phytase/ kg diet. Pigs fed the low –P diets plus Escherichia coli phytase addi on 2500 or 12500 U/kg of diet increasing bone breaking strength and ash weight. Pillai et al. ( 2006) observed that Escherichia coli phytase‐6 addi on at 250, 500, 1000 phytase units /kg improved carcass yield, breast yield, leg yield and tibia ash compared with birds fed the P‐inadequate diet. However, Attia et al. (2006a) found that phytase addi on at 1000 FTU/kg to Japanese quail diets containing 20% rice bran or 20% broken rice with two level of energy (2700, and 2800 kcal ME/kg), significantly decreased percentage intestinal, while significantly increased proventriculus percentage. In addition, supplemented phytase had no negative effect on chemical composition and physical characteristics of meat. 2.2.10 Effect of phytase on biochemical constituents of blood: Phytase had no effect on plasma total protein, total lipids, and cholesterol (Peter et al., 1997; Kornegay et al., 1998; A a et al., 2001). Results indicated that phytase supplementation to low P‐ diet increased plasma P. The increase in plasma phosphorus gives further evidence for improving of phytate phosphorus utilization by phytase (Broz et al., 1994; Mitchell and Edwards, 1996; Sebas an et al., 1996a, b; Lan et al., 2002). Phytase supplementation had no significant effect on plasma Ca (Edwards, 1993; El‐Deeb et al., 2000 and Lan et al., 2002 ) Zn (Sebastian et al., 1996a), copper (Sebastian et al., 1996a) and Mn (Lan et al., 2002) However, other studies have shown that phytase supplementation reduced plasma Ca (Sebastian et al., 1996a, b), Zn and Cu (Edwards, 1993). Mitchel and Edwards (1996) stated that plasma P increased as a result of phytase inclusion in diet for young broiler chickens at the rate of 600FTU/kg. Sebastan et al. (1996a) showed that phytase supplementation significantly (P<0.05) increased plasma P and reduced the Ca concentration. Sebastian et al. (1996b) concluded that phytase supplementation of a low­P broiler diet significantly (P<0.3) increased plasma P. The maximum level of plasma P was obtained with phytase at the 1.0% Ca level, but this value was not significantly different from the value obtained with phytase at the 0.6% Ca level. Attia et al. (2001) found that phytase addition at 700 FTU/kg to broiler diets, did not significantly affected of plasma total protein and total lipids constituents. Youssef et al. (2001) reported that phytase addition at 600, and 1000 FTU/kg to Gimmizah laying hens diets containing two levels of available phosphorous (0.40 and 0.25%) from 32­52 wk of age decreased plasma triglycerides with elevated P levels in presence of 1000 FTU
39 phytase /kg. In addition, plasma total protein and albumin were increased. On the other hand, plasma total lipids, plasma cholesterol, plasma AST, and ALT were not affected by any of the P levels with or without phytase presence. In addition, Jubarah et al. (2006) found that phytase treatment yield high serum and yolk total cholesterol, while had no significant affect on serum Cu and Zn. Viveros et al. (2002) found that phytase supplementation to low ­P diets increased plasma P level (P<0.01), and serum AST activity, reduced plasma Ca, and Mg, and reduced serum ALT, lactate dehydrogenase, alkaline phosphtase. However, plasma Zn was not affected by phytase supplementation. Qota et al. (2002) found that phytase addition at 500 FTU/kg to broiler diets, containing 10% soaked linseed cake did not affect plasma total protein, total lipids, triglycerides, and cholesterol. Lan et al. (2002) revealed that phytase supplementation had no significant effect on plasma Ca, Mn, while plasma P was increased due to phytase supplementation, while plasma Zn was increased only when 1000 U of phytase was supplemented. A a (2003a,b) found that phytase addi on at 600 FTU/kg to duckling diets containing different levels of lysine or methionine , did not affect plasma total protein, total lipids and cholesterol. Shirley and Edwards (2003) reported that supplemen ng phytase from 0 to 12000 FTU/kg diet significantly increased plasma P concentration. Cheng et al., (2004) reported that supplementation of phytase to 0.41% NPP basal diet fed to broilers from 7 to 28 d of age significantly increased plasma P concentrations. Abdo (2004) reported that there was no adverse effect on blood components due to addition of phytase, as well as it had no deleterious effects on liver function as measured by AST activity. Ghasemi et al. (2006) observed that Phytase inclusion at 800 U/kg of diet induced an improvement in concentration of serum P and protein (p<0.05). However, Ismail et al. (2006) found that supplemental phytase at 1000 FTU/kg had no effect on plasma constituents except for plasma total lipids which was increased significantly due to addition of phytase, but this without adverse effect on plasma cholesterol of Japanese quail. Frazinpour and Karimi (2006) reported that added phytase to diet by increasing NPP increased serum P, alkaline phosphytase, and total protein concentration and decreased serum Mg and did not affect Ca concentration. While, phytase did not significantly affect serum Ca, Mg, P, albumin and globulin of chicks fed adequate or suboptimum NPP in the growing and finishing period e.g. 0.38/0.36% and 0.45/0.43%,respectively.
40 3. MATERIALS AND METHODS The present study was conducted at private sector Poultry farm at Kafr El­Dawar area, Behera Governorate during the period of June to August 2005, whereas slaughter test, biochemical constituents of blood plasma and digestibility trials were done at Faculty of Agriculture –Damanhour. Meanwhile, meat quality traits and tibia analyses were done at Sakha Animal Research Laboratory to study the influence of two sources of microbial phytase on the performance of Sasso chicks fed diets containing suboptimum CP and suboptimum CP with ME levels. Productive performance, digestibility of nutrients, carcass quality, plasma constituents and economical evaluation were studied from one to 64 d of age. 3.1. Experimental birds, design, and diets: A total number of 420 unsexed day old Sasso chicks were housed in 60 floor pens (1.0 m ×1.0 m 2 / pens) furnished with rice hulls as a litter during the experimental period i.e. 1‐64 d of age. Each treatment consists of each five replicates of 12 chicks. 2 The experimental design was factorial (2 ×3 ) two (low CP diet, and low CP with low ME) by three phytase treatments (phytase unsupplemented control, phytase‐3 and phytase‐6) with adding a positive control. A basal all‐mash diet (positive control) was formulated to contain 21.2% CP, 2947 kcal ME, 0.84% methionine+cys ne, 1.24% lysine, 1% Ca and 0.49% available phosphorus during the starter period (1‐35 day of age; Table 4), 19.6% CP, 3023 kcal ME, 0.80% methionine+cys ne, 1.13% lysine, 0.90% Ca and 0.45% available phosphorus during grower period (37‐56 day of age, Table 5) and 18.0% CP, 3100 kcal ME, 0.74% methionine+cys ne, 1.00% lysine, 0.81% Ca and 0.40% available phosphorus during finisher period (57‐64day of age, Table 6). In the tested diets, CP was decreased by ~1% in one diet and CP and ME levels were decreased by 1% and 100 kcal ME/kg in another, respectively. Diets (Tables 4; 5 and 6) were formulated using NRC (1994) tables of feedstuffs, however, the nutrient requirements of Sasso chicks are not well known documented to the best of our knowledge, although their genetic potential for growth are better than new developed strains of chickens and lower than commercial broiler strains. The nutrient profiles of the experimental diets were met or exceed the recommendation of the Egyptian Ministry of Agriculture (Decision No. 1498, 1996). The low CP diet and low CP low ME diet were supplemented or not with two sources of microbial phytase e.g. fungal phytase‐3 Natuphos ®1 , and Escherichia coli phytase‐6 Phyzyme ®2 and 1 A product of BASF, Germany. Aspergillus niger phytase that is classified as a 3‐phytase, with hydrolysis of the phosphate moiety being ini ated at the 3‐position on the phytate molecule. It's recommended dose of use in broiler and turkey diets is 500 FTU of phytase/kg diet (BASF,1999). 2 A product of Danisco Animal Nutrition. Escherichia coli phytase is classified as a 6­phytase with hydrolysis of the phosphate moiety being initiated at the 6­position on the phytate molecule. Phyzyme® XP
41 resulting in six experimental diets in addition to the positive control. One unit (FTU) is equal to the enzyme ac vity that liberates 1 mmol ortho‐phosphate from 5.1 mmol of sodium phytate per minute at 37º C and pH 5.5. Its recommended dose of usage in broiler diets is 500 FTU. Available P and Ca percentage of phytase supplemented‐diets were not adjusted for phytase equivalent value in order to test the effect of two sources of phytase on protein and energy utilization in the presence of adequate dietary Ca and P levels. 3.2 Management: All mash form of feeds and clean water were offered ad. libitum throughout the experimental period, meanwhile birds were allo ed with 23:1 light‐dark cycle during 1‐64 days of age. Common management practice was used for brooding and rearing the birds. Vaccination and medical care were followed according to the common veterinary practice for broiler chicks. Chicks were kept under similar environmental, managerial, and hygienic condition. 3.3. Performance traits: 3.3.1. Live body weights (g): Birds were weighed (g) individually at day of age and at the end of the starter period (35 d of age), grower period (57 d of age) and the end of experimental period 64 d of age. Chicks were weighed in the morning before offering feeds. 3.3.2 Body weight gain (g): Body weight gains were calculated by subtracting body weight at end of each period from the initial body weight at the same period using individual record for each bird. 3.3.3 Feed (g / bird / period), protein (g / bird / period) and ME consumption (kcal/ bird/period): Feed intake was recorded every two weeks, according to the replicate­feeding system followed in the present work. Each group was provided daily with enough­pre weighed diet of its corresponding diet. The remainder and scattered feed as well as the consumed feed was weekly estimated for each replicate and thereafter, the average feed consumption from one to 35, 36 to 56, 57 to 64 and one to 64 of was calculated through division of group consumed by their chick numbers. The consumption of CP and ME was calculated by multiplying CP and ME of the experimental diets by its corresponding feed consumption. 3.3.4 Feed conversion ratio (g feed/g gain): for poultry. It's recommended dose of use in broiler and turkey diets is 100 g per tonne feed to provide 500 units of phytase/kg diet.
42 Feed to gain ratio was calculated in the form of units of feed consumption required to produce one unit of live body weight gain. 3.3.5 Protein conversion ratio (g protein/g gain): Protein to gain ratio was calculated in the form of units of protein consumption (g) required to produce one unit of live body weight gain. Table (4): Ingredients and chemical composition of the experimental basal diets (g/kg as fed basis) fed during the starter (1­35 days of age) Ingredients, g/Kg Starter diets Price LE/ton Control Low CP Low CP and ME Yellow corn 583.50 585.00 585.00 900 Soybean meal (%) 320.00 300.00 300.00 2400 Fish meal (%) 30.00 30.00 30.00 4000 Limestone 10.00 10.00 10.00 30 Dicalcium phosphate 18.00 18.00 18.00 1200 Vit+Min Premix 1 3.00 3.00 3.00 7000 NaCl 3.00 3.00 3.00 300 DL‐Methionine 1.50 1.50 1.50 21000 L‐Lysine (HCL) 1.00 1.00 1.00 18000 Vegetable oils 30.00 37.00 22.00 4000 Washed building sand 0.00 11.50 26.50 50.0 Total 1000 1000 1000 ….. Calculated and determined chemical composition,% Dry matter 2 89.61 89.70 89.53 ….. ME kcal/Kg, 3 2947 2952 2855 ….. CP, % 2 21.03 20.01 20.02 ….. Methionine,% 3 0.51 0.50 0.50 …..
43 SAA, % 3 0.85 0.82 0.82 ….. Lysine, % 3 1.24 1.19 1.19 ….. Calcium, % 3 0.99 0.99 0.99 ….. Av. P, % 3 0.49 0.49 0.49 ….. Crude fat,% 2 5.47 5.98 4.70 ….. Crude fibre,% 2 3.47 3.34 3.39 ….. Ash, % 2 9.24 10.02 11.21 NFE, % 2 60.79 60.65 60.68 Price LE / ton 1627 1609 1549 ….. ….. 1 Vit+Min mixture provides per kilogram of the diet: vitamin A (re nyl acetate) 24 mg, vitamin E (dl‐a‐ tocopheryl acetate) 20 mg, menadione 2.3 mg, Vitamin D3 (cholecalciferol) 0.05mg, riboflavin 5.5 mg, calcium pantothenate 12 mg, nico nic acid 50 mg, choline chloride 600 mg, vitamin B12 10 mg, vitamin B6 3 mg, thiamine 3 mg, folic acid 1 mg, d‐bio n 0.50 mg. Trace mineral (milligrams per kilogram of diet): Mn 80 Zn 60, Fe 35, Cu 8, Se 0.60. 2 Analyzed values. 3 Calculated values. 3.3.6 Metabolizable energy conversion ratio (kcal ME feed/g gain): Metabolizable energy to gain ratio was calculated in the form of units of metabolizable energy consumption (kcal) required to produce one unit of live body weight gain. Table (5): Ingredients and chemical composition of the experimental basal diets (g/Kg as fed basis) fed during the grower period (36­56 days of age) Ingredients, g/kg Grower diets Price LE/ton Control Low CP Low CP and ME Yellow corn 626.50 626.50 626.50 900 Soybean meal (%) 275.00 255.00 255.00 2400 Fish meal (%) 30.00 30.00 30.00 4000 Limestone 9.00 9.00 9.00 30 Dicalcium 16.00 16.50 16.50 1200
44 Vit+Min Premix 1 3.00 3.00 3.00 7000 NaCl 3.00 3.00 3.00 300 DL‐Methionine 1.50 1.50 1.50 21000 L‐Lysine (HCL) 1.00 1.00 1.00 18000 Vegetable oils 35.00 42.00 26.50 4000 Washed building sand 0.00 12.50 28.00 50.0 Total 1000 1000 1000 ….. Calculated and determined chemical composition,% Dry matter 2 89.87 89.63 89.76 ….. ME kcal/Kg, 3 3023 3024 2923 ….. CP, % 2 19.49 18.51 18.48 ….. Methionine,% 3 0.49 0.48 0.48 ….. SAA, % 3 0.80 0.78 0.78 ….. Lysine, % 3 1.13 1.08 1.08 ….. Calcium, % 3 0.90 0.90 0.90 ….. Av. P, % 3 0.45 0.45 0.45 ….. Crude fat,% 2 6.21 6.74 5.26 ….. Crude fibre,% 2 3.31 3.24 3.20 ….. Ash, % 2 9.30 10.28 10.19 NFE, % 2 61.69 61.23 62.87 Price LE / ton 1575 1556 1495 1 ….. ….. As shown in Table 1. 2 Analyzed values. 3 Calculated values. 3.3.7 Mortality rate(MR)%: Mortality rate was calculated as the percentage of birds dead in each treatment during the experimental period. 3.3.8 Apparent digestibility of nutrients:
45 To test the effect of the experimental diets and sources of phytase supplementations on diges bility of crude protein, crude fat, crude fiber and nitrogen reten on, at 64 day of age, six experimental chicks of each treatment as three replicates of two males each were gone under digestibility evaluation using total collection method (A a, 1986). Chicks were fasted for 24 h. then they were fed on their corresponding experimental diets for 72 h, in which feed consumption and excreta voided, were accurately determined. The excreta was collected for each replicate, cleaned from feathers and feed then weighed, dried in a forced air oven at 70º C for 36 h. Samples were then finally ground and placed in screw‐top glass jars until analyses. Table (6): Ingredients and chemical composition of the experimental basal diets (g/Kg as fed basis) fed during the finisher period (57­64 days of age) Ingredients, g/kg Finisher diets Price LE/ton Control Low CP Low CP and ME Yellow corn 630.00 630.00 630.00 900 Soybean meal(%) 282.50 260.00 260.00 2400 Limestone(%) 9.00 9.00 9.00 30 Dicalcium 17.00 17.00 17.00 1200 Vit+Min Premix 1 3.00 3.00 3.00 7000 NaCl 3.00 3.00 3.00 300 DL‐Methionine 1.50 1.50 1.50 21000 L‐Lysine(HCL) 1.00 1.00 1.00 18000 Vegetable oils 53.00 61.00 46.00 4000 Washed building sand 0.00 14.50 29.50 50.0 Total 1000 1000 1000 ….. Calculated and determined chemical composition,% Dry matter 2 89.57 89.69 89.84 ….. ME kcal/Kg, 3 3091 3092 2995 ….. CP, % 2 17.80 16.79 16.81 ….. Methionine,% 3 0.44 0.42 0.42 ….. SAA, % 3 0.74 0.71 0.70 …..
46 1 Lysine, % 3 1.00 0.94 0.94 ….. Calcium, % 3 0.81 0.80 0.80 ….. Av. P, % 3 0.40 0.39 0.39 ….. Crude fat,% 2 7.63 7.98 6.97 ….. Crude fibre,% 2 3.33 3.24 3.26 ….. Ash, % 2 9.18 10.19 11.63 NFE, % 2 62.06 61.80 61.33 Price LE / ton 1549 1528 1469 ….. ….. as shown in Table 1. 2 Analyzed values. 3 Calculated values. The procedure described by Jakobsen et al. (1960) was used for separating fecal nitrogen from urine nitrogen (endogenous and urine) in excreta samples. Total nitrogen, fecal nitrogen, fat, crude fiber and crude ash contents of the excrement as well as those of feed were determined according to AOAC (1990), and expressed on a dry matter basis. The apparent digestibility of dry matter, crude protein, fat, crude fiber and apparent retention of ash (%) was calculated by dividing the daily amount retained (g/d) by amount intake (g/d). The daily amount is equal to the amount intake (percentage nutrient in feed × amount of feed consumed) minus that voided in the excreta (percentage nutrient in excreta, except for nitrogen, which the fecal nitrogen was used × amount of excreta voided). 3.3.9 Slaughter test: 3.3.9.1 Slaughter procedure: At 64 day of age, six birds (3 males and 3 females) were taken randomly from each treatment, weighed after fasting overnight, slaughtered, and their feathers were plucked and the total inedible parts (head, legs and inedible viscera) were taken aside. Then, the remaining carcass (dressed carcasses) was weighed and divided into the front and the hind parts and weighed and expressed to live body weight. The internal organs including liver, pancreas, spleen and length of intestines and cecum were measured and expressed to live body weight. Abdominal fat including those located in the abdominal cavity and that surrounding the intestines and around the heart were separated, weighed, and expressed to live body weight. 3.3.9.2 Chemical composition of muscle: A sample of 50 % of breast muscle + 50 % of thigh muscle was weighed and kept in an electric drying oven at 70° C for 24 h until constant weight. The dried flesh was finely ground through a suitable mixer to pass through a sieve (1­mm²) and then carefully mixed. The air­ dried samples were kept into well tight glass container for subsequent analysis.
47 3.3.10 Tibia characteristics: The right tibia was removed of the slaughtered chicks, cleaned from tissues, set in hexane for 48 h to remove fat and dried in an oven for 24 h until constant weight. Their length (mm), width (mm), weight (g), ash, Ca and phosphorus were determined to study the effect of dietary treatments on bone mineralization. Length and width of tibia were determined using vernier caliber. Ash percentage of defatted tibia and its relative Ca and P contents were determined after ashing at 600º C, according to the methods of AOAC. (1990). 3.3.11Analytical methods: Feed samples of the experimental diets from the starter, grower and finisher feeds as well as from the flesh of experimental birds were chemically analyzed for DM, CP, EE, CF, and ash according to the official methods of AOAC (1990). The nitrogen free extract was determined by subtracting the sum of all fractions mentioned above from the DM. 3.3.12 Physical characteristics of meat: Physical characteristics of meat (50 % breast and 50% thigh meat) were carried out using fresh samples of meat as follows: 3.3.12.1 Water Holding Capacity (WHC) and Tenderness: The ability of meat to hold water (WHC) and tenderness of meat were measured according to the method of Volvoinskaiaa and Kelman (1962) in which 0.3 g minced meat tissues were put under an ashless filter paper and pressed for 10 min using 1 kg weight. On the filter paper, two zones were formed. Their surface areas were measured by the planimeter. The WHC was calculated by subtracting the internal zone form the outer zone. The internal zone is due to the meat pressing only indicating the tenderness. 3.3.12.2. pH value: The pH value was measured by pH meter as described by Aitken et al. (1962) as follows: About 10.0 g of prepared samples from meat and drip were blended with 50 ml of distilled water for 10 minutes, and then pH value was measured. 3.3.12.3. Color intensity: Color intensity of meat and drip were determined according to the method of Husani et al. (1950) as follows: 10 g of samples were shaken with 50 ml distilled water in dark room for 10 minutes then, filtered and the color intensity (absorbency) was measured photometrically at 543 mm. 3.3.13. Biochemical constituents of blood plasma: Blood samples were collected of six birds of each treatment in heparinzed tubes at 64 d of age. Plasma was separated by centrifugation at 3000 rpm for 15 minutes and stored at ­20 o C until analysis. Concentrations of plasma Ca (Sendroy, 1944), inorganic P (Gomorri, 1942) and alkaline phosphatase (Belfield and Goldberg, 1971) were determined. Liver enzymes AST and ALT were determined according to Retiman and Frankel (1957). Concentrations of total protein (Henry et al., 1974), albumin (Doumas et al., 1977), total lipids (Chabrol and Charonnat, 1973), total cholesterol (Watson,
48 1960) were determined. Globulin was calculated by differences between total protein and albumin. 3.3.14. Production index and economical efficiency: Production index was calculated according to North and Bell (1990) using the following equation: Production index= Body weight gain (Ib)/ feed conversion)*100 Economical evaluation for all experimental diets was made. Economical efficiency was calculated as described by Zeweil . (1996) using the following steps for growing trials: 1. Average body weight gain (kg). 2. Price of kg body weight at time being of terminating of the experiment (8 LE). 3. Total revenue /chick (LE)=1x2 4. Total feed intake /chick (kg) 5. Price/kg feed (LE) 6. Total feed cost/chick (LE)=4x5 7. Fixed cost/chick (3.0LE) 8. Total cost/chick (LE)=6+7 9. Net revenue (LE)=3­8 10. Economical efficiency (EE)= (Net revenue/ total costs)×100 3.4. Statistical Analysis: Data were analyzed using the GLM procedure of Statistical Analysis Software (SAS) version 6.11 (SASâ Institute, 1985, Cary, NC, USA) using two­way factorial design (two types of diets by two types of phytase besides the positive control). Mean difference at P£0.05 was tested using Student­Newman­Keuls­Test.
49 4. RESULTS AND DISCUSSION 4.1 Growth performance of Sasso chickens: 4.1.1 Effect of dietary suboptimum CP and suboptimum CP with ME level: The results for the main effect of optimum feeding suboptimum CP and suboptimum CP and ME diet on growth of Sasso chicks are shown in Table (7). The average one­d old BW of the Sasso chicks ranged from 44.1 to 45.9 g, and the statistical analyses revealed that there were no significant differences in initial BW among different experimental groups in one­d old­ BW indicating a random distribution of the chicks among the experimental treatments. From one‐d old to 35 d of age, BWG was not significantly affected by feeding suboptimal CP and suboptimal CP and ME levels compared to the positive control. This showing that decreasing CP level from ~21.0 to ~20% without or with further decrease in ME level by ~100 kcal had no negative on growth of Sasso chicks during 1‐35 d of age. This may indicate that 20% CP with either 2952 or 2855 kcal ME/ kg diet is adequate for growth of Sasso chicks during 1‐35 d of age. On the other hand, decreased CP level alone without or with decreasing ME level significantly decreased BWG by 27.8 and 27.2% during 36‐56 d of age compared to the positive control. This indicated that 19.50% CP with 3023 kcal ME is op mum for growth of Sasso chicks during 36‐56 d of age. However, feeding suboptimum CP diet or suboptimum CP and ME diet significantly increased growth from 57‐64 d of age of Sasso chicks by 51.4 and 47.0%, respec vely. This indicated that 16.8% CP with 3100 kcal ME or 3000 kcal ME is adequate for Sasso chicks during 57‐64 d of age. However, this substantial increase in growth of the suboptimum CP or suboptimum CP with ME diet could be explained by phenomea of compensatory growth because of the decrease in growth in the former period (Attia et al., 1995 and Saleh et al., 1996). On the other hand, there were no significant differences in growth of chicks for the whole experimental period (1‐64 d of age), however, low‐protein or low prtein‐low energy decreased BWG by108.5 and 96.5 gm lower than positive control . Similarly, Khalifah (2001) found no significant differences between 18, 16, and 14% CP level in BW of Gimmizah and Golden Montazah strains.
50 Table7. Body weight gain of Sasso chickens as affected by type of phytase and/or suboptimum‐ protein level or suboptimum‐protein and energy level Treatments BW gain ,g 1‐35d 36‐56d 57‐64d 1‐64 d Final BW g MR % 1‐64 Main effect of diet Positive control 700.7 776.7 a 280.0 b 1757.4 1801.7 0 Low‐protein 664.8 560.8 b 423.9 a 1660.9 1694.1 2.0 Low‐Protein‐low energy 685.1 565.2 b 411.5 a 1648.9 1705.6 2.0 SEM 26.2 34.1 33.0 54.3 55.1 ‐‐‐ NS 0.001 0.001 NS NS ‐‐‐ No phytase 690.0 636.1 a 385.5 b 1711.7 1756.7 0 Natuphos 685.5 578.3 b 424.4 a 1653.0 1697.9 1.0 Phyzyme 654.7 545.0 b 390.3 b 1622.6 1667.2 3.0 SEM 26.2 34.1 33.0 54.3 55.1 ‐‐‐ NS 0.04 0.04 NS NS ‐‐‐ Positive control 700.7 776.7 a 280.1 b 1757.5 1801.7 0 Low‐protein× No phytase 690.8 560.8 b 450.8 a 1702.4 1748.3 0 Low‐protein× Natuphos 667.9 486.7 b 477.1 a 1631.7 1674.6 1
P Value Main effect of type of phytase P Value Interaction between phytase and diet 51 Low‐protein× Phyzyme 635.8 635.0 ab 343.2 ab 1614.0 1658.5 1 Low‐protein‐low energyNo phytase 678.6 570.8 b 425.0 ab 1674.4 1720.0 0 Low‐protein‐low energy× Natuphos 703.2 603.3 b 370.7 ab 1677.2 1721.6 2 Low‐protein‐low energy× Phyzyme 673.6 521.5 b 436.7 a 1631.8 1675.8 0 SEM 40.0 51.9 50.4 82.8 84.5 ‐‐‐ NS 0.001 0.0001 NS NS ‐‐‐
P Value a‐b , means within a column under the same treatment with different superscripts are significantly different. NS, not significant In accordance with the present findings, El‐Sakkaf (1995) indicated that protein effect is age dependent variable, since it had a significant effect on BW of Alexandria, Gimmizah, Mandarah and Silver Montazah at 4 wk of age, and this impact was diminished at 8 wk of age. However, Shaldam (2003) and Attia et al. (2003c) found that high CP level in the diet for Gimmiziah and Gold Montazah and local hybrid chicks had a significant positive influence on growth of chicks. Similarly, Attia et al. (2001 and 2006 a,b) and Driver et al. (2005) revealed that reducing CP and ME level in broiler and Japanese quail diets adversely affect growth significantly. Along the same line, Venäläinen et al. (2006) found that broilers fed high (2868 kcal ME) grew more rapidly and were heavier than those given were low ME (2629 kcal ME). In conclusion, Sasso chicks could be fed diet containing 20% CP with 2855 kcal, 18.5% CP with 2923 kcal and 16.8% CP and 3000 kcal ME from one­d old to 35, 36 to 56 and 57 to 64 d of age without adverse effects on growth. However, it should be mentioned that the literature related to the CP and ME requirements of Sasso chicks are scare. 4.1.2 Effect of type of phytase: The results displayed in Table (7) showed the main effect of type of phytase on growth of Sasso chicks from one­d old to 64 d of age. The results indicated that phytase type had no significant effect on growth of chicks from 1­35 d of age and for the complete experimental period from one­d old to 64 d of age. It should be noticed, however, either Natuphos (Phytase­3) or Phyzyme (Phytase­6) decreased significantly growth of chicks from 36 to 56 d of age compared to the unsupplemented control. However, Natuphos increased significantly growth of chicks from 57 to 64 d of age compared to the unsupplemented control and Phyzyme supplemented groups (Table7). The increase over the unsupplemented control and Phyzyme­supplemented group was 10.1 and 8.7%, respectively. El­Medany and El­Afif (2002) showed that fungal phytase­3 addition at 750 FTU/kg to broiler diets containing different levels of NPP (0.30; and 0.45) and CP (19.5; 23%) increased BWG by 11% of low CP diet. Moreover, adding phytase to normal CP level (23%) increased BWG by 4% compared with unsupplemented groups, feed intake 52 was increased and FCR was improved by 8 and 3%; and 3 and 0.6% by adding phytase to 19.5 and 23% CP respectively. The positive effect of Natuphos during 57­64 d of age where fishmeal was withdrawn and Ca and P levels were substantial decreased of the experimental diets may be however, due to the release of nutrient complex of phytate molecule as well as the other side activities of the enzymes produced by phytase­producing organisms (Attia et al., 2001; 2003b; Kies et al., 2001; El­Ghamry et al., 2005). In this regard, Wu et al. (2003 and 2004) found that a microbial phytase produced by solid state fermentation and containing significant activates of ß­glucanase and xylanase was as effective as xylanase in improving the performance of broiler chickens fed wheat­based diets containing adequate level of P. In the literature, the effect of phytase is independent of its mineral effect and associated with reduced digesta viscosity, increased AME and decreased relative weight and length of the small intestine (Bedford, 1996; Sebastian et al., 1998; Camden et al., 2001; Brufau et al., 2002; Wu et al., 2003; Dilger et al., 2004). Phytase has been shown to increase availability of minerals, protein/amino acid and ME for broilers and resulted in improved growth performance (Kies et al., 2001; Attia et al., 2001; 2003c, Abd­Elsamee et al., 2002; Hussein, 2006 and Rezaei et al 2007). At the end of the experimental, BW and BWG for the complete experimental period were not significantly affected by type of phytase supplemented. Similarly, Payne et al. (2005) and Veum et al. (2006) observed that there were no differences in the efficacy of the E. coli or P. lycii phytase at 500 U /kg of low­P diet for growth performance of pigs. It could be concluded that phytase supplementation did not improve growth of Sasso chicks fed corn­soybean meal and fishmeal diet containing adequate Ca and P levels during the most of the experimental period. Furthermore, Ghasemi et al. (2006) concluded that the effect of phytase on BW and FCR was less pronounced in the phytase adequate diet. 4.1.3 Interaction between phytase type and diet: Data for the interaction between diet containing suboptimum CP level alone or suboptimum CP and ME level and type of phytase are shown in Table (7). The results showed that growth of Sasso chicks during 1­35 d of age and for the whole period (1­64 d of age) was not significantly affected by the interaction between diet and type of phytase. There were significant interaction between diet and type of phytase from 36­56 and 57­64 d of age. Results revealed that Phyzyme numerically improved growth of chicks fed low CP dietbetween 36­56 d by 13.2% compared to its negative control, thus there were no significant difference from the positive control. Results from 57­64 d of age indicated that Natuphos or Phyzyme had no beneficial effect when added over their negative controls containing either suboptimum CP level or suboptimum CP with ME level. However, Natuphos­supplemented diet containing suboptimum CP level and Phyzyme­supplemented diet containing suboptimum CP with ME had significantly better growth than the positive control, although did not significantly different from the negative controls. The improvement over the positive control was 70.3 and 55.9%, respectively. Furthermore, it
53 should be mentioned, however, that this improvement might be explained, in the view of phenomena of compensatory growth as these groups had recovded the least growth during the former experimental period. On the other hand, sach improvement may be due to the decrease, in the Ca and P during 57­64d of age period (Lantzsch, 1989; Heinzl, 1996; El­ Deeb et al., 2000), and/or the withdrawal of fishmeal, as high available Ca and P source, of the experimental diets. On the other hand, the different mechanisms of two phytases on growth of chicks from 57­64 d of age may be explained by their activity in the gut. It is well know that the optima pH for E. Coli phytase­6 is lower (2.5 : 3.5) and had more resistance to pepsin than Natuphos phytase­3 (2.5:5.5) which enable the former to had more activity and recovery than phytase­3 in the stomach the primary site for phytase activity (Yi and Kornegay, 1996). Yu et al. (2004) showed that exogenous fungal phytase protein (phytase­6) was detected in the phytase diet as well as in the digesta of crop; gizzard, duodenum and jejunum, but not ileum of broiler chickens fed the phytase diet. This suggested that the exogenous phytase might be digested and degraded upon arrival at the terminal end of the small intestinal of broiler chicks fed phytase diet. Similar results were reported by Liebert et al. (1993) who demonstrated that detectable exogenous phytase activity amounted to 25­50% in the crop; 10­25% in the proventriculus and no activity in the small intestine in 3­5 wk­old chicks and concluded that crop and proventriculus in poultry are the major functional sites of exogenous phytase. In general, the residence time of the digesta in the crop, proventriculus and gizzard is about 3 h, thus allowing relatively longer periods for phytase to react with dietary phytate (Yi and Kornegay, 1996). The results about the positive effect of phytase on the utilization of CP/amino acid and ME as noticed in the last experimental period are in general agreement with the reports by (Ravindran, 1999a; Attia et al.,2001; Kies et al., 2001; Abd­Elsamee, 2002; El­ Medany and El­Afifi, 2002; Attia 2003a; Rutherfurd et al., 2004 and El­Ghamry et al., 2005). Sebastian et al. (1998) and Kies et al. (2001) reviewed the negative effect of phytate molecule on protein and energy utilization and its inhibitory effects on pepsin, trypsin and a­amylase. Phytate may form complexes with protein/amino acid as those inherited in feedstuffs (Ravindran et al., 1995) or those de novo formatted in the digestive tract (Jongbloed et al., 1997) and with free amino acids in the digestive tract (Rutherfurd et al., 1997) and resulted in decreasing protein utilization (Selle et al 2006 and Choct, 2006). In this regard, Kornegay et al. (1998) evaluated the impact of phytase on performance, ileal amino acid digestibility of broilers and observed that phytase at 300 to 400 FTU/kg restored the reduced performance and improved ileal amino acid digestibility in phosphorus deficient diet. Phytase supplementation to broiler diets containing suboptimum CP/amino acid and energy levels improved growth performance (Ravindran et al., 1999; Attia et al., 2001; El­Medany and El­Afifi, 2002; Abd­Elsamee, 2002 and Attia, 2003a). Kies et al. (2001) concluded that phytase supplementation at 500 FTU/kg diet improved the digestibility of amino acids and crude protein by 1–3%. However, Boling­Frankenbach et al. (2001) showed that 1200 FTU of phytase did not significantly increase protein utilization of several feed ingredients as assayed by a protein efficiency ratio of diets containing varied Ca from 0.95 to 1.5 and nonphytate phosphorus from 0.35 to 0.675%. In the present work, phytase supplementation as either 3­ phytase (Natuphos, A. niger) or 6­phytase (E. coli) did not significantly improve the overall growth performance of Sasso chicks from 1­64 d of age. Similarly, Akyurek et al. (2005) showed that phytase­ 6 (Ronozyme) did not affect BWG of broiler chicks from 1­21 d of age.
54 The absence of significant effect of phytase on growth of Sasso chicks during the most of the experimental periods may be due to high Ca and NPP contents of the experimental diets since diets were not adjusted for phytase equivalent value. It is well known that Ca: P ratio and Ca level interfere with phytase activity in the gut due to increasing its pH value, and the optimum Ca level for phytase activity is <0.75% and at higher pH there is formation of Ca phytate, which precipitates, thus can't be attacked by phytase (Lantzsch, 1989; Heinzl, 1996 and El­Deeb et al., 2000). In addition, the increase in the Ca:P ratio has linearly decreased the effect of phytase on P­ retention (Qian et al., 1997; Lei and Stahl, 2000, Lou et al., 1999). However, Schöner et al. (1993) concluded that Natupos­phytase was not adversely affected by increasing Ca levels, however, to obtain maximum breakdown of phytate it is recommended not to supplement Ca at rates higher than physiologically necessary. In virto studies revealed that high phosphorus was found to repress the synthesis of acid phosphatases and phytases, while limiting phosphate conditions result in their expression (Vats and Banerjee, 2004). Han and Gallagher (1987) found that a sharp decline in phytase production by A. niger even at 0.05% phosphorus in the medium with absolute no production at 0.1% and the above, indicating the end product inhibition in phytase synthesis. For more details and excellent review for factors effecting phytase efficacy, please see Vats and Banerjee (2004). The results of the last experimental periods, are similar to those reported by Zanini and Sazzad (1999), Sohail and Roland, (1999) and Ghasemi et al. (2006) who indicated that the effect of phytase­3 (Natuphos) increased BW of broiler at lower NPP level, but not at the higher NPP­ level. However, recent results with E. coli phytase­6 showed an improved growth of broiler and pigs fed P deficient diets and the effect of E. coli phytase was greater than that of Natuphos and Ronozyme phytase (Augspurger et al., 2003; Augspurger and Baker, 2004 ; Jendza et al., 2005; Veum et al., 2006 and Pillai et al., 2006). The contradiction between the above mentioned results and that reported herein may be explained based on the dietary Ca and P levels, age of chicks, dose of phytase, energy and protein /amino acids fed. Moreover, lack of explanation for the negative effect of the suboptimum dietary protein and energy level used herein on performance of Sasso chicks expect for the that observed from 1­35 d at age may be due to the lack of appropriate guide of the nutrient requirement for this type of chicks. All in all, Sasso chicks fed diet containing suboptimum CP or suboptimum CP and energy with adequate Ca and P level without or with either phytase­3 or ­6 was exhibited similar growth to those fed the control diet containing adequate (optimum) CP and ME levels. 4.2. Mortality: There were only four chicks dead during the experimental period (Table7). Thus, total number of dead birds amounted to 1.0% of the experimental birds, which was within a permissible range. Furthermore, the postmortem investigation indicated that mortality was not related to dietary treatments. These results are similar to those reported by Attia et al. (1998; 2001 and 2006) and Akyurek et al. (2005). The authors concluded that protein and energy levels and phytase additions had no significant effect on mortality of chickens. 4.3 Feed intake (g/bird/period):
55 4.3.1 Effect of dietary suboptimum CP and suboptimum CP with ME level: The results for the effect of dietary suboptimum CP and suboptimum CP with ME levels on feed intake of Sasso chicks are shown in Table (8). Feed intake of Sasso chicks from one d­ old to 35 and 57to 64 d of age and for the whole experimental period from one­d old to 64 d of age was significantly affected by feeding suboptimum CP and suboptimum CP with ME levels compared to the positive control . The results indicated that there was a linear decrease in feed intake with suboptimum CP level and decreasing protein with energy levels during 1­35 d of age. Meanwhile, decreasing protein level alone and protein with energy level had similar negative effect of feed intake from 57 to 64 and 1 to 64 d of age. The decrease in feed intake due to feeding low protein and low protein with energy diet for the complete experimental period amounted to 5.0% and 5.3%, respectively compared to the positive control group. This decrease in feed intake could explain the decrease in growth showed due to feeding suboptimum CP and protein­energy diets observed from one to 35 and 1­64 d of age. Similarly, Abd El­Samee (2001), Shaldam (2003) and Driver et al. (2005) found that protein level had a significant positive effect on feed intake of native strains and broiler chicks. In accordance with the present results, Venäläinen et al. (2006) found that broilers fed high (2868 kcal ME) consumed more feed and were heavier than those given low ME (2629 kcal ME). Similarly results of , Uni et al. (1995) and Noy and Sklan (1996) indicated that feed intake is the major factor affecting growth. However, it was expected that chicks will tend to compensate for the decrease in protein and energy levels by increasing feed intake consumption (NRC, 1994 and Attia et al., 2001), the opposite trend was observed. On the other hand, Zanini and Sazzad (1999) indicated that energy level of 2800 and 3000kcal ME/kg diet did not affect feed intake of broiler chicks. It seems that the effect of CP and ME levels on feed intake is age dependent variable, since there was no significant effect during the growing period, and the significant effect was affected by decreasing protein and energy levels during the starter period and then during the finisher period. Table 8. Feed intake of Sasso chickens as affected by type of phytase and/or suboptimum‐ protein level or suboptimum‐protein and energy level Treatments Feed intake( g/ bird/period ) 1‐35 d 36‐56 d 57‐64 d 1‐64 d Positive control 1375.0 a 1622.5 1026.5 a 4024.0 a Low‐protein 1311.6 b 1567.5 944.1 b 3823.7 b Low‐Protein‐low energy 1296.8 c 1561.7 954.1 b 3812.6 b SEM 2.84 6.09 5.26 12.1 P Value 0.001 NS 0.0009 0.0001
Main effect of diet 56 Main effect of type of phytase No phytase 1338.8 a 1615.0 a 991.6 a 3945.4 a Natuphos 1304.4 b 1565.0 b 951.1 b 3820.5 b Phyzyme 1287.5 c 1517.5 c 922.0 c 3727.0 c SEM 2.84 6.09 5.26 12.1 P Value 0.001 0.0001 0.0002 0.0001 Positive control 1375.0 a 1622.5 a 1026.5 4024.0 a Low‐protein× No phytase 1343.5 b 1640.0 a 975.8 3959.3 b Low‐protein× Natuphos 1306.3 c 1557.0 bc 940.0 3803.8 cd Low‐protein× Phyzyme 1285.0 d 1505.0 d 916.5 3706.5 d Low‐protein‐low energy× No phytase 1298.0 cd 1582.5 b 972.5 3853.0 c Low‐protein‐low energy × Natuphos 1302.5 cd 1572.5 b 962.3 3837.3 c Low‐protein‐low energy × Phyzyme 1290.0 d 1530.0 c 927.5 3747.5 d 4.34 9.31 8.03 18.5 0.0003 0.003 NS 0.005 Interaction between phytase and diet SEM P Value a‐d , means within a column under the same treatment with different superscripts are significantly different. NS, not significant 4.3.2 Effect of type of phytase: The results displayed in Table (8) showed the effect of type of phytase on feed intake of Sasso chickens from one­d old to 64 d of age. The results indicated that type of phytase had a significant negative effect on feed intake throughout the experimental period as well as the complete experimental period too. It is clear that Phyzyme (phytase­6) had a stronger negative effect (P>0.05) than Natuphos (phytase­3) on feed intake. The decrease for the complete experimental period was3.2 and 5.5%, respectively, compared to the positive control. However, Akyurek et al. (2005) found that phytase­3 (Natuphos) and phytase­6 (Ronozyme) had no significant effect on feed intake of broiler chicks and Japanese quail. Moreover, Panye et al. (2006) showed that type of fungal phytase had no significant effect of feed intake of broiler chicks. However, Attia et al. (2006a,b) found that phytase decreased significantly feed intake of Japanese quail compared to the control group.
57 In the literature, the effect of phytase on feed intake is contradictory; for example, Attia (2003a) showed that the effect of phytase on feed intake is dependent on ducklings' age, where a stimulating effect was observed during the starter­grower period and negative effect was shown during the finishing period, which resulted in diminishing of responses to phytase supplementation. However, El­Medany and El­Afifi (2002), Abd­EL Samee (2002), Dilger et al. (2004), Ibrahim (2004) and Zyla et al. (2004) observed that phytase increased feed intake of broiler chicks. However, phytase addition at 1000 FTU decreased significantly feed intake compared to 500 FTU (Dosoky, 2003), showing that the effect of phytase is dose dependent. 4.3.3 Interaction between phytase type and diet: Data for the interaction between type of phytase and diet on feed intake are shown in Table (8). The results showed that feed intake of Sasso chicks from 57 to 64 d of age was not significantly affected by the interaction between phytase type and diet. However, there was a significant interaction between type of phytase and diet on feed intake from one­d old to 35, 36 to 56 and 1 to 64 d of age. The results indicated that feeding low protein diet decreased significantly feed intake, and decreasing energy level besides decreasing protein level further significantly decreased feed intake from one­d old to 35 d of age (Table 8). These decreases were 2.4 and 5.6% , respectively, compared to the positive control. Meanwhile, Natuphos and Phyzyme supplementations to the low protein diet decreased significantly feed intake by 2.8 and 4.4%, respectively, compared to its negative control. However, the effect of phyzyme was significantly greater than that of Natuphos (Table 8). It should be mentioned, however, that neither Natuphos nor Phyzyme affect feed intake of the suboptimum CP and suboptimum CP with ME diet. Data indicated that low protein diet had no significant effect on feed intake from 36 to 56 d of age, while decreasing protein and energy level had a significant negative effect on feed intake compared to the positive control and low protein diet alone. Natuphos and Phyzyme supplementation to the low protein diet had significant negative similar effects on feed intake from 36 to 56 d of age compared to their negative control and the positive control, too. Phyzyme supplementation to the suboptimum CP­energy had significant negative effect on feed intake compared to its negative control, however, the effect of Phyzyme was stronger in the suboptimum CP diet compared to the suboptimum CP and energy diet (8.2 vs. 3.3%; Table 8). For the complete experimental period, there was a negative effect of feeding suboptimum CP and suboptimum CP with ME levels; with the later effect was significantly stronger (4.2 vs. 1.6%). Natuphos and Phyzyme supplementations to the suboptimum CP diet had significant negative effects on feed intake from one­ d old to 64 d of age compared to their negative control. However, the effect of Phyzyme was stronger compared to the effect of Natuphos (3.9 vs. 2.7%; Table 8). On the other hand, only Phyzyme supplementation to the suboptimum CP­energy had significant negative effect on feed intake compared to its negative control. It seems, therefore that the effect of type of phytase on feed intake is dependent on protein and energy contents of the experimental diet and age of chicks. These results are similar to those reported by Attia (2003b) who found that the effect of phytase on feed intake is dependent on dietary methionine level. Similarly, Attia et al. (2006b) found that the effect of enzyme supplementation on feed intake of Japanese quail is dependent on source and level of dietary energy. Similarly, Ibrahim (2004) showed a three­way interaction between phytase addition and available
58 phosphorus level and source of phosphorus. Similarly, Ghasemi et al. (2006) found a significant interaction between phytase and nonphytate phosphorus of the diet, as phytase had a clear effect on NPP deficient diet (50% of the phosphorus recommended level). However, Zanini and Sazzad (1999) found that the interaction between phytase supplementation and energy level was not significant for feed intake of broiler chicks. 4.4 Protein intake (g/bird/period): 4.4.1 Effect of dietary suboptimum CP and suboptimum CP with ME levels: The results for the effect of dietary suboptimum CP and suboptimum CP and ME levels on protein intake of Sasso chicks are shown in Table (9). Intake of CP of Sasso chicks from one­d old to 35 and 57to 64 d of age and for the complete experimental period from one­d old to 64 d of age was significantly affected by feeding suboptimum CP and suboptimum CP with ME levels. The results indicated that there was a linear decrease in protein intake with decreasing CP level and decreasing CP with ME levels from one d old to 35 d of age compared to the positive control. Meanwhile, decreasing CP level alone and CP with ME level had similar negative effect ON CP intake from 36 to 56, 57 to 64 and one­d old to 64 d of age except her the peroid from 1 to 35 d of age ,where group fed low protein –low energy diet had lower value than throse fed low protein diet alone . The decrease in CP intake due to feeding suboptimum CP and suboptimum CP with ME diet for the complete experimental period amounted to 9.8% and 10.1%, respectively compared to the positive control group. These decreases in protein intake could explain the decrease in growth by 5.5 and 6.2% respectively, showed herein due to feeding suboptimum CP and protein with energy diets though not significant. Similarly, Attia et al. (2001) and Abd El­Samee et al. (2001) found that CP intake decreased with decreasing dietary CP levels in broiler diets. It seems that the effect of CP and CP with ME levels on CP intake is age dependent variable, since there are significant differences between treatments during the starter period, and the differences was diminished then after (Table 9).
59 Table 9. Protein intake of Sasso chickens as affected by type of phytase and/or suboptimum‐ protein level or suboptimum‐protein and energy level Treatments Protein intake( g/ bird/period ) 1‐35 d 36‐56 d 57‐64 d 1‐64 d Positive control 289.2 a 316.2 a 182.7 a 788.1 a Low‐protein 262.4 b 290.1 b 158.4 b 711.1 b Low‐Protein‐low energy 259.6 c 288.6 b 160.4 b 708.6 b SEM 0.583 1.14 0.892 2.23 P Value 0.0001 0.0001 0.0001 0.0001 No phytase 272.6 a 304.1 a 170.0 a 746.7 a Natuphos 261.1 b 289.4 b 159.8 b 710.3 b Phyzyme 257.7 c 280.7 c 154.9 c 693.3 c SEM 0.583 1.14 0.892 2.23 P Value 0.0001 0.0001 0.0002 0.0001 Main effect of diet Main effect of type of phytase Interaction between phytase and diet
60 Positive control 289.2 a 316.2 a 182.7 788.1 a Low‐protein× No phytase 268.8 b 303.6 b 163.8 736.2 b Low‐protein× Natuphos 261.4 c 288.3 c 157.8 707.5 cd Low‐protein× Phyzyme 257.1 d 278.6 d 153.9 689.6 d Low‐protein‐low energy× No phytase 259.9 c 292.4 c 163.5 715.8 c Low‐protein‐low energy × Natuphos 260.8 c 290.6 c 161.8 713.1 c Low‐protein‐low energy × Phyzyme 258.3 cd 282.7 d 155.9 696.9 d SEM 0.889 1.74 1.36 3.41 P Value 0.0003 0.003 NS 0.005 a‐c , means within a column under the same treatment with different superscripts are significantly different. NS, not significant 4.4.2 Effect of type of phytase: The data found in Table (9) showed the effect of type of phytase on CP intake of Sasso chickens from one­d old to 64 d of age. The results indicated that type of phytase had a significant negative effect on CP intake throughout the experimental period as well as the complete experimental period, too from one­d old to 64 d of age . It is clear that Phyzyme (phytase­6) had a stronger negative effect than Natuphos (phytase­3) on protein intake. The decrease for the complete experimental period was 4.9 and 7.2% , respectively, compared to the positive control, and these decreases parallels the non­significant decrease by 3.4 and 5.2% respectively in growth of chicks fed Natuphos and Phyzyme­supplemented diets (Table 7). 4.4.3 Interaction between phytase type and diet: Data for the interaction between type of phytase and diet on CP intake are shown in Table (9). The results showed that CP intake of Sasso chicks from 57 to 64 d of age was not significantly affected by the interaction between phytase type and dietary composition. However, there was a significant interaction between type of phytase and dietary composition on CP intake from one­d old to 35, 36 to 56 and 1 to 64 d of age. The results indicated that from one­d old to 35 d of age, feeding low CP diet decreased significantly CP intake (7.1%), and decreasing ME level besides decreasing CP level further decreased (10.1%) significantly CP intake, compared to the positive control (Table 8). Meanwhile, Natuphos and P hyzyme supplementations to the suboptimum CP diet decreased significantly CP intake by 2.8 and 4.4% respectively, compared to its negative control. However, the decrease due to Phyzyme was significantly greater than that of Natuphos (Table 9). There were no significant differences due to phytases in the suboptimum CP with ME diets compared to their respective controls, and this group had lower protein intake than the positive control.
61 Data indicated that low protein diet had a significant effect on protein intake (4%) from 36 to 56 d of age, and further decreased energy level significantly decreased protein intake by 7.5 and 3.7% , respectively compared to the positive control and low protein diet alone. Natuphos and Phyzyme supplementation to the suboptimum CP diet had significant negative effects on feed intake from 36 to 56 d of age compared to their negative control. However, the influence of Phyzyme was significantly greater than Natuphos (8.2 vs.5.1%). Phyzyme supplementation to the suboptimum CP with ME diet had a significant negative effect on feed intake compared to its negative control. However, the effect of Phyzyme was stronger in the low CP diet compared to the low CP and ME diet (8.2 vs. 3.3%), although difference was not significant (Table 9). For the complete experimental period, there was a negative effect of feeding low protein and low protein with energy levels, with the later effect was significantly stronger (9.2 vs. 6.6%). Natuphos and Phyzyme supplementations to the low protein diet had significant similar negative effects on protein intake from one­d old to 64 d of age compared to their negative control. However, only Phyzyme supplementation to the suboptimum CP with ME diet had a significant negative effect on protein intake compared to its negative control. On the other hand, the effect of phytases was similar in the low protein and low protein and energy diets when the corresponding groups were compared (Table 9). In fact, the decrease in CP intake could explain the insignificant decrease in growth showed of Sasso chicks at the end of the experimental period(Table 7). 4.5 Metabolizable energy intake (kcal ME /chick/period): 4.5.1 Effect of dietary suboptimum CP and suboptimum CP and ME levels: The results for the effect of dietary suboptimum CP and suboptimum CP and ME levels on ME intake of Sasso chicks are shown in Table (10). Energy intake of Sasso chicks from one­d old to 35, 36to 56 and 57 to 64 d of age and for the complete experimental period from one­d old to 64 d of age was significantly affected by feeding low CP and low CP with ME levels. The results indicated that there was a linear decrease in ME intake with decreasing protein level and decreasing protein with energy levels from one­d old to 35, 36 to 56 and 1 to 64 d of age. Meanwhile, decreasing CP level alone, CP with ME level had similar negative effect of ME intake from 57 to 64. The decrease in ME intake due to feeding suboptimum CP and suboptimum CP with ME diet for the complete experimental period amounted to 4.9% and 8.3%, respectively compared to the positive control group. These decreases in ME intake, besides the decrease in protein intakes could explain the decrease in growth by 5.5 and 6.2%, respectively, observed herein due to feeding low protein and protein­energy diets though not significant. Similarly, Attia et al. (2001 and 2006b) found that ME intake decreased with decreasing dietary energy levels in broiler and Japanese quail diets, respectively. Table 10. Metabolizable energy intake of Sasso chickens as affected by type of phytase and/or suboptimum‐ protein level or suboptimum‐protein and energy level Treatments Energy intake( g/ bird/period )
62 1‐35 d 36‐56 d 57‐64 d 1‐64 d Positive control 4052.1 a 4904.8 a 3172.9 a 12129.9 a Low‐protein 3871.8 b 4740.1 b 2919.1 b 11531.0 b Low‐Protein‐low energy 3702.5 c 4564.8 c 2857.5 b 11124.7 c 8.32 17.9 15.9 36.1 0.0001 0.0001 0.0001 0.0001 No phytase 3907.9 a 4829.9 a 3034.2 a 11772.1 a Natuphos 3787.3 b 4653.2 b 2894.2 b 11334.7 b Phyzyme 3738.1 c 4511.7 c 2805.8 c 11055.6 c 8.32 17.9 15.9 36.1 0.0001 0.0001 0.0001 0.0001 Positive control 4052.1 a 4904.8 a 3172.0 12129.9 a Low‐protein× No phytase 3966.0 b 4959.4 a 3017.0 11194.4 d Low‐protein× Natuphos 3856.0 c 4709.9 b 2906.5 11472.4 c Low‐protein× Phyzyme 3793.3 d 4551.1 cd 2833.8 11178.3 d Low‐protein‐low energy× No phytase 3705.8 e 4625.6 bc 2912.6 11244.1 d Low‐protein‐low energy × Natuphos 3718.6 e 4596.4 c 2881.9 11197.0 d Low‐protein‐low energy × Phyzyme 3682.9 e 4472.2 d 2777.9 10933.0 e 12.7 27.4 24.3 55.0 0.0002 0.002 NS 0.004 Main effect of diet SEM P Value Main effect of type of phytase SEM P Value Interaction between phytase and diet SEM P Value a‐c , means within a column under the same treatment with different superscripts are significantly different. NS, not significant 4.5.2 Effect of type of phytase:
63 The data found in Table (10) showed the effect of type of phytase on ME of Sasso chickens from one­d old to 64 d of age. The results indicated that type of phytase had a significant linear negative effect on ME intake compared to the unsupplemented control throughout the experimental period as well as the complete experimental period too from one­d old to 64 d of age. It is clear that Phyzyme (phytase­6) had a stronger adverse effect than Natuphos (phytase­3) on ME intake. The decrease for the complete experimental period was 3.7 and6.1 %, respectively, compared to the positive control. These decreases in addition to that observed in protein intake parallels the non­significant decrease by 3.4 and 5.2%, respectively in growth of chicks fed Natuphos and phyzyme­supplemented diets (Table 8). Similarly, Attia et al. (2006b) reported that phytase­6 (Ronozyme) significantly decreased energy intake of Japanese quail chicks. 4.5.3 Interaction between phytase type and diet: Data for the interaction between type of phytase and dietary composition on ME intake are shown in Table (10). The results showed that ME intake of Sasso chicks from 57 to 64 d of age was not significantly affected by the interaction between phytase type and dietary composition. However, there was a significant interaction between type of phytase and dietary composition on ME intake from one­d old to 35, 36 to 56 and 1 to 64 d of age. The results indicated that from one­d old to 35 d of age, feeding low CP diet decreased significantly ME intake (2.1%), and further decreased ME level besides CP level substantial decreased significantly ME intake (8.5%) compared to the positive control (Table 10). Difference between the low CP and low CP with ME groups was also significant. Meanwhile, Natuphos and Phyzyme supplementations to the low protein diet decreased significantly ME intake by 2.8 and 4.4% , respectively, compared to its negative control, showing significantly greater effect of Phyzyme (Table 10). There were no significant differences due to phytases supplementation to in the low CP with ME diets, and all had lowered ME intake than the positive control. The results showed that phytase had stronger effect on low CP with ME diet than low CP diet alone (Table 10). Data indicated that low CP diet had no significant effect on ME intake from 36 to 56 d of age, however, further decreased ME level, besides CP level significantly decreased ME intake by 5.7 and 6.7%, respectively compared to the positive control and suboptimum CP diet alone. Natuphos and Phyzyme supplementations to the suboptimum CP diet had significant negative effects on ME intake from 36 to 56 d of age compared to their negative control. However, the influence of Phyzyme was significantly stronger (8.2 vs. 5.0%). Phyzyme supplementation to the suboptimum CP with ME diet had significant negative effect on ME intake compared to its negative control and Natuphos supplemented group. However, the effect of phyzyme was stronger in the suboptimum CP diet compared to the low CP with ME diet (8.2 vs. 3.3%; Table 10). However, difference was not significant when the corresponding groups were compared. In contrast, Natuphos supplemented low­ CP with ME diet had significantly lowered ME intake than its counterpart group feed low CP diet alone. For the complete experimental period, there was a significant similar (7.3 vs. 7.7%) negative effect of feeding low CP and low CP with ME levels. Natuphos supplementation to the suboptimum CP diet increased significantly ME intake from one­d old to 64 d of age compared to their negative control, while Phyzyme had no effect in the same diet. However, only Phyzyme supplementation to the low CP with ME energy diet had significant negative effect on ME intake compared to its negative control (2.8%) and the
64 rest of treatment groups. On the other hand, the effect of Phyzyme was stronger in the low CP with ME diets than the low CP diet alone (Table10). In fact, the decrease in ME intake in addition to that in CP intake could explain the insignificant decrease in growth showed of Sasso chicks at the end of the experimental period (Table 7). 4.6 Feed conversion ratio (FCR) : 4.6.1 Effect of dietary suboptimum CP and protein with energy level: The results for the main effect of suboptimum CP and low protein with low energy level on FCR of Sasso chicks are shown in Table (11). FCR of Sasso chicks during 36­56 and 57­ 64 d of age was negatively affected by decreasing protein and protein with energy level (Table 11). Feeding suboptimum CP diet and low protein with energy level significantly impaired FCR compared to the positive control from 36­56 d of age. These results are similar to those reported by Attia et al. (2001 and 2006b) with broilers and Japanese quail. On the other hand, feeding low protein diet or low protein with energy diet improved significantly FCR by 38.6 and 36.5% compared to the positive control from 57­64 d of age. For the complete experimental period, there was no significant influence of low dietary protein and low protein with energy level on FCR and the values were nearly similar. The lack of significant differences due to feeding low CP and CP with ME levels indicated that Sasso chicks could be fed diets containing 20% CP with 2855 kcal ME, 19.5% CP with 3025 kcal ME and 16.8% CP and 3000 kcal ME from 1­35, 36­56 and 57­ 64 d of age without adverse effect on FCR. Attia et al. (1998) and Driver et al. (2005) found that better FCR was recorded by broilers fed high­CP high ME diets than those fed on low CP with ME diets. Similarly, Venäläinen et al. (2006) found that broilers fed high (2832 kcal /kg diet) was better than those given low ME (2629 kcal /kg diet). Along the same line, Abo El­ Maaty (2002) and Shaldam (2003) found that there were no significant differences in FCR due to feeding different protein levels, however, chicks fed high protein diet had slightly better feed utilization than those fed low protein diet. In conclusion, FCR was not affected significantly by decreasing protein level by 1% and energy level by 100 kcal in the starter, growing and finishing diets for Sasso chicks. 4.6.2 Effect of type of phytase: The results displayed in Table (11) showed the effect of type of phytase on FCR of Sasso chicks from one­d old to 64 d of age. Results indicated that during the most of the experimental period , type of phytase did not significantly affect FCR of Sasso chicks. However, Natuphos supplemented­group had significantly worse FCR from 36 to 56 d of age compared to the other groups.
65 Table 11. Feed conversion ratio (g feed/ g gain)of Sasso chickens as affected by type of phytase and/or suboptimum‐ protein level or suboptimum‐protein and energy level Treatments FCR (g feed/ g gain) 1‐35 36‐56 57‐64 1‐64 Positive control 1.96 2.09 b 3.70 a 2.29 Low‐protein 1.97 2.84 a 2.27 b 2.32 Low‐Protein‐low energy 1.89 2.78 a 2.35 b 2.31 SEM 0.231 0.049 0.066 0.027 NS 0.0001 0.0001 Ns No phytase 1.94 2.60 b 2.72 2.31 Natuphos 1.91 2.91 a 2.30 2.33
Main effect of diet P Value Main effect of type of phytase 66 Phyzyme 1.97 2.66 b 2.42 2.30 SEM 0.231 0.049 0.066 0.027 NS 0.026 NS Positive control 1.96 2.09 e 3.70 a 2.29 Low‐protein× No phytase 1.95 2.94 b 2.17 c 2.33 Low‐protein× Natuphos 1.96 3.21 a 1.98 c 2.33 Low‐protein× Phyzyme 2.02 2.37 d 2.68 b 2.30 Low‐protein‐low energy× No phytase 1.91 2.78 bc 2.29 c 2.30 Low‐protein‐low energy × Natuphos 1.85 2.62 c 2.62 b 2.32 Low‐protein‐low energy × Phyzyme 1.92 2.94 b 2.15 c 2.31 SEM 0.035 0.074 0.100 0.037 NS 0.0001 0.0006 NS P Value NS Interaction between phytase and diet P Value a‐c means within a column under the same treatment with different superscripts are significantly different. NS means not significant The present results are similar to those obtained by Zanini and Sazzad (1999), Sohail and Roland (1999) and Ghasemi et al. (2006) who indicated that Natuphos (phytase­3) improved FCR of broiler at lower NPP level, but not at the higher NPP level. Recently, Akyurek et al. (2005) and Rezaei et al. (2007) showed that Ronozyme (phytase­ 6) and Ntauphos (phytase­3) did not affect FCR of broiler chicks from 1 to 21 d of age and 1­49 d of age respectively. On the other hand, E. coli phytase­6 supplementation to the broiler and pigs diets containing reduced levels of phosphorus improved FCR (Augspurger et al., 2003; Augspurger and Baker, 2004; Jendza et al., 2005; Veum et al., 2006 and Pillai et al., 2006). Furthermore, the effect of E. coli phytase was greater than that of Natuphos and Ronozyme phytase, and both fungal phytases showed similar effect (Augspurger et al., 2003; Augspurger and Baker, 2004; Jendza et al., 2005; Veum et al., 2006; Pillai et al., 2006 and Payne et al., 2005). The results indicated that type of phytase did not significantly affect FCR of Sasso chicks for the complete experimental period. 4.6.3 Interaction between phytase type and diet: Results for the interaction between type of phytase and dietary composition on FCR during the experimental period are displayed in Table (11).
67 The results showed that FCR of Sasso chicks from one­d old to 35 d of age as well as from one­d old to 64 d of age was not significantly affected by the interaction between type of phytase and dietary composition. On the other hand, there was significant influence of the interaction on FCR from 36 to 56 and 57 to 64 d of age. Results obtained during 35­ 65d of age indicated that Phyzyme supplementation to the low protein diet significantly improved FCR by 19.4 and 26.2%, respectively compared to the negative control and Natuphos supplemented group. On the other hand, phytases had no significant effect on FCR in the diet containing low protein and protein with energy level. Results otained during 57­64 dof age indicated that feeding low protein diet without or with Natuphos or Phyzyme resulted in better FCR than the positive control, however, Natuphos supplemented group showed better values (37.3%) than Phyzyme supplemented group. Similarly, decreasing protein with energy level without or with Natuphos and phyzyme resulted in better FCR than the positive control. However, Phyzyme supplemented group showed better FCR (17.9%) than Natuphos supplemented groups, which in contrary to those observed in the suboptimum CP level.For the cpmplete period (1­64d ), it should be noticed however, that FCR of the low protein level and low protein with energy level was similar, and phytases did not yield further improvement. All in all, the data indicated that 500 FTU of fungal (Natupos) or E. coli (Phyzyme) phytase did not improve FCR of Sasso chicks fed low protein and suboptimum CP and energy levels and containing adequate Ca and P levels. These results are inline with those reported by Zanini and Sazzad (1999), Sohail and Roland, (1999) and Akyurek et al. (2005). They showed that phytase­3 (Natuphos) and phytase­6 (Ronozyme) improved FCR of broiler at lower NPP level, but not at the higher P level. 4.7 Protein conversion ratio: 4.7.1 Effect of dietary suboptimum CP and protein with energy levels: The results for the main effect of low CP and low CP with ME level on CP conversion of Sasso chicks are shown in Table (12). Protein conversion of Sasso chicks during all experimental periods was significantly affected by decreasing CP and CP with ME level compared to the positive control (Table12). Feeding low CP with ME diet significantly, improved CP conversion compared to the positive control from one­d old to 35 d of age. Meanwhile, suboptimum CP diet alone showed intermediate values. On the other hand, feeding low CP diet or suboptimum CP with ME diets impaired significantly CP conversion from 36­56 d of age compared to the positive control, however, the contrary was shown from 57 to 64 d of age. For the complete experimental period, there was a significant similar improvement in CP conversion due to feeding low protein and low CP with ME diet (Table12). The improvement in CP conversion was 16.6 and 17.7%, respectively compared to the positive control. The improvement in protein conversion could be due to the decrease in protein intake, it was well documented that chicks tend to improve nutrient utilization with decreasing nutrient intake (Scott et al., 1982 and Shaldam, 2003). Along the same line, Attia et al. (2003c) found that there was a significant improvement in CP conversion due to decreasing dietary CP level. In conclusion, CP conversion was significantly improved by decreasing CP level by 1% with ME level by 100 kcal from one­d old to 64 d of age for Sasso chicks.
68 Table12. Protein conversion (g protein/ g gain)of Sasso chickens as affected by type of phytase and/or suboptimum‐ protein level or suboptimum‐protein with energy level Treatments Protein conversion (g feed/ g gain) 1‐35 36‐56 57‐64 1‐64 Positive control 0.413 a 0.408 b 1.04 a 0.621 a Low‐protein 0.495 ab 0.526 a 0.633 b 0.518 b Low‐Protein‐low energy 0.380 b 0.514 a 0.640 b 0.511 b SEM 8.17 0.009 0.018 0.008 P Value 0.01 0.0001 0.0001 0.001 No phytase 0.395 0.488 b 0.751 0.545 Natuphos 0.381 0.539 a 0.629 0.517 Phyzyme 0.395 0.492 b 0.676 0.521 SEM 8.17 0.009 0.018 0.008 NS 0.02 NS NS Positive control 0.413 0.408 c 1.04 a 0.621 Low‐protein× No phytase 0.390 0.544 b 0.597 c 0.510 Low‐protein× Natuphos 0.392 0.594 a 0.550 c 0.512 Low‐protein× Phyzyme 0.405 0.439 c 0.752 b 0.532 Low‐protein‐low energy× No phytase 0.383 0.513 bc 0.612 c 0.503 Low‐protein‐low energy × Natuphos 0.371 0.484 c 0.708 b 0.521 Low‐protein‐low energy × Phyzyme 0.385 0.544 b 0.600 c 0.509 SEM 12.5 0.14 0.27 0.012 NS 0.0001 0.0006 NS
Main effect of diet Main effect of type of phytase P Value Interaction between phytase and diet P Value 69 a‐c means within a column under the same treatment with different superscripts are significantly different. NS means not significant 4.7.2 Effect of type of phytase: The results shown in Table (12) showed the effect of type of phytase on CP conversion of Sasso chicks from one­d old to 64 d of age. Results revealed that type of phytase had no significant effect on protein conversion during the most of the experimental period. However, Phyzyme supplemented ­group had significantly better CP conversion compared to Natuphos only from 36 to 56 d of age. In addition, the positive control showed similar trend (Table 12). Protein conversion ratio for the complete experimental period of both Natuphos and Phyzyme supplemented­groups was better than the unsupplemented control, although difference was not significant. The present results are in party agreement with those reported by Zanini and Sazzad (1999), Kies et al. (2001), Attia et al. (2001 and 2004) and Abd El­Samee (2002) who reported that phytase­3 (Natuphos) had similar results with E­Coli phytase­6 with boiler chicks supplementation and significantly improved the utilization of protein/amino acids. On the other hand, Peter et al. (2000), Peter and Baker (2001), Boling­Frankenbach et al. (2001), Cowieson et al. (2006b) and Ravindran et al 2006., Jendza et al (2005) ., Augspurger and Baker (2004) and Veum et al. (2006) found that phytase E. Coli had no significant effect on protein absorption and amino acid digestibility and protein efficiency ratio of chicks. The present hypothesis that if phytase has an effect on amino acid digestibility, it is most likely the result of the phytase hydrolyzing the phosphate groups off of the inositol ring, thereby destroying or preventing the formation of protein­phytate complexes (Kies et al., 2001). This effect has been inconsistently approved as observed in the above mentioned results. In this regard, the effect of phytase is related to phosphorus/phytic level and phytase dose (Ravindran et al., 2006; Pillai et al., 2006 and Waston et al., 2006) The results indicated that phytase had no signifiicant effect on protein conversion ratio of Sasso chicks form 1 to 64 d of age, and this agree with the results of Yi et al. (1996c), and Ravindran et al. (2000) that phytase was more efficacious for improving amino acid digestibility in chicks fed lower non­phytate phosphorus level than chicks fed higher non­phytate phosphorus level. 4.7.3 Interaction between phytase type and dietary composition: Results for the interaction between type of phytase and diet on protein conversion during the experimental period are displayed in Table (12). The results showed that protein conversion of Sasso chicks from one­d old to 35 d of age as well as from one­d old to 64 d of age were not significantly affected by the interaction between type of phytase and diet. On the other hand, there was significant influence of the interaction between phytase type and diet from 36 to 56 and 57 to 64 d of age. It was found that suboptimum CP and ME diet had no significant effect on CP conversion of Sasso chicks compared to the positive control and the low CP diet alone. Results indicated that Phyzyme significantly improved FCR of protein­reduced diet by 19.4 and 26.1%, respectively compared to the corresponding negative control and
70 Natuphos supplemented group. On the other hand, Natuphos improved CP conversion compared to the Phyzyme supplemented groups of diet containing low CP with ME level. Results indicated that from 57to 64 d of age feeding low CP diet without or with Natuphos and Phyzyme resulted in better CP conversion than the positive control, however, Natuphos supplemented group showed better values (26.9%) than Phyzyme supplemented group although it did not significantly differ from the negative control. Similarly, decreasing CP and ME levels without or with Natuphos and Phyzyme resulted in better FCR than the positive control. However, Phyzyme supplemented group showed better FCR (15.3%) than Natuphos supplemented groups, which in contrary to those observed in the low CP level. This indicated that the effect of type of phytase depends on dietary composition.Allover the experimental period (1­64d), it should be noticed however, that CP conversion of the low CP level and low CP with ME level was similar, and phytase as either phytase­3 (Fungal) or phytase ­6 (E. coli) did not yield further improvement over these groups. All in all, the data indicated that 500 FTU of fungal or E. coli phytase did not improve FCR of Sasso chicks fed low CP and low CP with ME levels and containing adequate Ca and P levels from one­ d old to 64 d of age. However, the best CP conversion was observed for group fed low CP with ME diet. These results are in line with those reported by Jendza et al. (2005), Augspurger and Baker (2004) and Veum et al. (2006). 4.8 Metabolizable energy conversion ratio: 4.8.1 Effect of dietary suboptimum CP and protein with energy levels: The results for the main effect of low protein and low CP with ME level on ME conversion of Sasso chicks are shown in Table (13). Energy conversion of Sasso chicks of all experimental periods was significantly affected by decreasing CP and CP with ME levels (Table 13). Feeding low­ CP and low­ME diet significantly improved ME conversion compared to the positive control and low­CP diet from one­d old to 35 d of age. Meanwhile, low CP diet did not improve ME conversion compared to the positive control. On the other hand, feeding suboptimum CP diet or suboptimum CP with ME diets impaired significantly ME conversion from 36 to 56 d of age compared to the positive control, however, the contrary was shown from 57 to 64 d of age. For the complete experimental period, there was a significant similar improvement in ME conversion due to feeding low CP and low CP with ME level (Table13). The improvement in CP conversion was 8.9 and 12.6% respectively compared to the positive control. The improvement in ME conversion could be due to the decrease in ME intake, it was well demonstrated that chicks tend to improve nutrient utilization with decreasing nutrient intake (Scott et al., 1982 and Attia, 1986). Along the same line, Attia et al. (2001 and 2006b) found that there was a significant improvement in ME conversion due to feeding low energy levels in broilers and Japanese quail diets. In conclusion, ME conversion was significantly improved by decreasing protein level by 1% and energy level by 100 kcal during the most of the experimental periods of Sasso chicks.
71 Table 13. Energy conversion (Kcal / g gain) of Sasso chickens as affected by type of phytase and/or suboptimum‐ protein level or suboptimum‐protein with energy level Treatments ME conversion (g feed/ g gain) 1‐35 36‐56 57‐64 1‐64 Main effect of diet Positive control 5.83 a 6.33 b 11.5 a 7.85 a Low‐protein 5.79 a 8.59 a 7.04 b 7.15 b Low‐Protein‐low energy 5.42 b 8.13 a 7.05 b 6.86 b SEM 0.067 0.145 0.201 0.095 P Value 0.0016 0.0001 0.0001 0.0008 5.67 7.78 b 8.33 7.26
Main effect of type of phytase No phytase 72 Natuphos 5.54 8.68 a 6.98 7.06 Phyzyme 5.73 7.89 b 7.37 6.99 SEM 0.067 0.145 0.201 0.095 P Value NS 0.02 NS NS Positive control 5.79 6.33 e 11.45 a 7.85 Low‐protein× No phytase 5.75 8.88 b 6.70 c 7.11 Low‐protein× Natuphos 5.78 9.70 a 6.12 c 7.20 Low‐protein× Phyzyme 5.97 7.17 d 8.29 b 7.14 Low‐protein‐low energy× No phytase 5.47 8.12 c 6.86 c 6.81 Low‐protein‐low energy × Natuphos 5.29 7.66 cd 7.83 bc 6.93 Low‐protein‐low energy × Phyzyme 5.49 8.60 bc 6.45 c 6.85 SEM 0.102 0.220 0.307 0.146 P Value NS 0.0001 0.0005 NS Interaction between phytase and diet a‐c means within a column under the same treatment with different superscripts are significantly different. NS means not significant 4.8.2 Effect of type of phytase: The results displayed in Table (13) exhibited the effect of type of phytase on ME conversion of Sasso chicks from one­d old to 64 d of age. Results indicated that during the most of the experimental period type of phytase did not significantly affect ME of Sasso chicks. However, Natuphos supplemented­ group had significantly worse FCR from 36 to 56 d of age than other groups. Energy conversion ratio for the complete experimental period was not significantly affected by phytase type, and the values were nearly similar. However, Natuphos and Phyzyme had better 2.8 and 3.7% energy conversion compared to the control group, although these differences were not significant. These results are in party agreement with those obtained by Sebastian et al. (1998), Zanini and Sazzad (1999) and Attia et al. (2001 and 2004), Camden et al. (2001) and Kies et al. (2001) who indicated that phytase­ 3 (Natuphos) improved ME utilization by ~3%. On the other hand, Liebert et al (2005) found that phytase did not improve ME conversion of broiler chicks. The results indicated that type of phytase did not significantly affect energy conversion of Sasso chicks for the complete experimental period.
73 4.8.3 Interaction between phytase type and diet: Results for the interaction between type of phytase and dietary composition on ME conversion during the experimental period are displayed in Table (13). The results showed that ME conversion of Sasso chicks from 1 d up to 35 d of age as well as from 1­64 d of age were not significantly affected by the interaction between type of phytase and diet constituents of CP and ME levels. On the other hand, there was significant influence of the interaction between type of phytase and CP and ME contents of experimental diet from 36 to 56 and 57 to 64 d of age. Results indicated that Phyzyme supplementation to the low CP diet during the 36­56 d of age significantly improved ME conversion by 19.3 and 26.1% respectively compared to the negative control and Natuphos supplemented group. On the other hand, phytases had no significant effect on FCR in the diet containing low CP and low CP with ME levels. It is clear that feeding low protein and energy diet significantly improved ME conversion by 8.6% compared to corresponding group fed low protein diet alone (Table 13). Results from 57 to 64 d of age indicated that feeding low protein diet without or with Natuphos and phyzyme resulted in better ME conversion than the positive control, however, Natuphos supplemented group showed significantly better ME conversion (26.2%) than Phyzyme supplemented group. Similarly, decreasing protein and energy levels without or with Natuphos and Phyzyme resulted in better FCR than the positive control however, Phyzyme supplemented group had numerically (P<0.05) better FCR (17.6%) than Natuphos supplemented groups. This is in contrary to those observed in the low protein level. For the overall period (1­64 d) , it should be noticed however, that ME conversion of the low protein diet and low protein with energy level was similar, and phytases did not yield further improvement over the unsupplemented control. The present results are similar to those reported by Wu et al.(2004) and Oduguwa et al (2007). Olukosi et al. (2007) who found that phytase had no significant effect on digestible energy. All in all, the data indicated that 500 FTU of fungal phytase ­3 or E. coli phytase­6 did not improve ME conversion of Sasso chicks fed suboptimum CP and suboptimum CP with ME levels and containing adequate Ca and P levels. However, the best ME conversion was noticed for group fed unsupplemented low CP with ME level. 4.9 Digestibility coefficients of nutrients: 4.9.1 Effect of dietary suboptimum CP and protein and energy level: The results for the effect of feeding suboptimum CP and suboptimum CP with ME level on nutrients digestibility of Sasso chicks are shown in Table (14). Although it was expected that decreasing protein or decreasing protein with energy would improve digestibility of nutrients, there was no significant effect on digestibility of DM, CF, EE, CP, apparent retention of ash, fecal nitrogen and metabolic nitrogen. On the other hand, 6.7 and 5.9% decreases in excreta­N was noticed due to feeding low CP and low CP with ME diet, respectively This indicates a decrease in the N­emission of poultry house and poultry manure due to feeding low CP and low CP and low CP with ME level. Disagreements results were found by Abd­Elsamee (2002) who indicated that increasing dietary crude protein significantly increased the digestibility coefficient of OM, CP, EE, and nitrogen retention. However, Attia et al. (2001), Shaldam (2003) and Attia et al. (2003c) found
74 that there was no significant improvement in crude protein, ether extract, crude fibre and ash due to decreasing protein and protein and energy levels. It could be concluded that decreasing protein by 1% without or with energy level by 100 kcal in Sasso containing diets did not significantly affect digestibility of nutrients, however, excreta N was decreased by~6%, which could have a beneficial effect on the environment. 4.9.2 Effect of type of phytase: The data displayed in Table (14) showed the effect of type of phytase on nutrient digestibility of Sasso chickens. Type of phytase had no significant effect on digestibility of EE and excreta N. The results indicated that phytase significantly improved ash retention, digestibility coefficients of DM, CF and CP and the later effect was due to the improvement in the retention of fecal nitrogen rather than metabolic nitrogen (Table 14). It should be mentioned that both type of phytase showed equal potentiality. Similarly, Veum et al. (2006) observed that there were no differences in the efficacy of the E. coli or P. lycii phytase at 500 U /kg of low­P diet for apparent percentage absorption of N, GE, DM, Zn, Fe, or Cu.
The effect of phytase on protein digestibility could be attributed to the improvement in the digestibility of amino acids. In this regard, Farrell et al. (1993) indicated that phytase supplementation to broiler diets improved N retention by 2.7% and MEn by 2.3% and this reflects partly in the increase in DM digestibility, and true ileal amino acid digestibility in the presence of microbial phytase (Attia et al., 2001 and Rutherfurd et al., 2004). The latter authors indicated that true ileal amino acid digestibility was significantly greater in the presence of microbial phytase­3 (Natuphos) for all the amino acids examined with the exception of methionine, tyrosine, histidine, and tryptophan. The mean increase in true ileal amino acid digestibility was 3.4%. The surprising finding of phytase was on apparent digestibility of crude fiber found herein (Table 14) that could proof extra benefits from hydrolyses of cell walls, which increases ME value (Ravindran, 1999b; Zanini and Sazzad, 1999; Attia et al., 2001; Kies et al, 2001; Abd­Elsamee, 2002; Attia et al., 2003a; Wu et al., 2004 and El­Ghamry et al., 2005). Similarly, Shakmak (2003) indicated that Ronozyme phytase­6 addition to quail diets increased significantly CP, EE, CF, and OM and calculated ME compared to the control diet. On the other hand, the effect of phytase on CP and ME utilization was not confirmed by the results by Wu et al. (2004) and Oduguwa et al. (2007). However, Cowieson et al. (2006a) reported that phytase reduced endogens amino acids loss.
75 Digestibility,% Treatments DM CF Ash Dig.,% retenti CP on,% EE Nitrogen,% Excre Fecal ta Metab olic. Main effect of diet Positive control 80.4 29.0 79.6 31.4 75.5 5.41 a 2.52 2.88 Low‐protein 81.3 31.4 79.9 32.6 77.5 5.05 b 2.37 2.69 Low‐Protein‐low energy 80.5 31.2 80.5 32.6 77.1 5.09 b 2.39 2.70 SEM 0.38 0.59 0.59 0.29 0.39 0.05 0.63 0.06 NS NS NS NS NS 0.006 NS NS No phytase 79.1 b 28.7 b 79.3 31.4 b 75.6 b 5.20 2.57 a 2.63 Natuphos 82.3 a 33.1 a 80.7 33.0 a 78.0 a 5.08 2.26 b 2.81 Phyzyme 82.0 a 32.3 a 80.7 33.3 a 78.2 a 5.04 2.27 b 2.76 SEM 0.380 0.591 0.590 0.290 0.387 0.050 0.030 0.063 P Value 0.0001 0.002 NS 0.0005 0.001 NS 0.001 NS P Value Main effect of type of phytase Interaction between phytase and diet Positive control 80.4 29.0 79.6 31.4 75.5 5.41 2.52 2.88 Low‐protein× No phytase 79.1 29.0 78.8 31.4 76.0 5.14 2.55 2.58 Low‐protein× Natuphos 82.4 33.1 80.4 33.0 78.1 5.02 2.26 2.75 Low‐protein× Phyzyme 82.4 32.1 80.5 33.4 78.6 5.01 2.28 2.73 Low‐protein‐low energy× No phytase 77.9 28.0 79.7 31.5 75.5 5.06 2.61 2.44
76 Low‐protein‐low energy × Natuphos 82.1 33.1 81.0 33.0 78.0 5.14 2.26 2.87 Low‐protein‐low energy × Phyzyme 81.5 32.5 81.0 33.2 77.9 5.07 2.27 2.79 SEM 0.59 0.90 0.91 0.44 0.45 0.09 0.04 0.09 NS NS NS NS NS NS NS NS
P Value Table 14. Apparent digestibility of nutrients of Sasso chickens as affected by type of phytase and/or suboptimum‐ protein level or suboptimum‐protein and energy level a‐b means within a column under the same treatment with different superscripts are significantly different. NS, not significant. It could be concluded that phytase supplementation either as Natuphos phytase­3 or Phyzyme phytase­6 to Sasso chicken diets containing reducing level of protein and energy and containing adequate Ca and P levels similarly increased digestibility of DM, CF, CP, and decreased fecal N and increased ash retention which could have a beneficial effect on the environment. The results of Jendza et al. (2006) with broilers indicated that E. coli phytase­6 did not affect N absorption or digestibility. On the other hand, Akyurek et al. (2005) indicated that phytase­6 (Ronozyme) had no significant effect on digestibility DM, CP, while significantly improved digestibility of EE, decreased crude ash, Ca and P of the excreta. The present results are in line with those reported by Payne et al. (2005) that Natuphos phytase­3 and Ronozyme phytase­6 had similar effect on animal's performance. 4.9.3 Interaction between phytase type and diet: Data for the interaction between type of phytase and dietary constituents of CP and ME level on digestibility of DM, CF, EE, CP, and retention of ash as well as excreta N, fecal and metabolic N are displayed in Table (14). The results showed that digestibility of all nutrients as well as ash retention, excreta N, fecal N and metabolic N were not significantly affected by the interaction between type of phytase and diet. This means that the effect of type of phytase and diet containing suboptimum CP and suboptimum CP with ME levels showed herein are independent variable. In conclusion, there was no significant interaction between type of phytase and diet on nutrient digestibility and fecal and metabolic N. 4.10 Carcass yield and body organs: 4.10.1 Effect of dietary suboptimum CP and protein with energy level: Data for the effect of feeding suboptimum CP and CP with ME level on carcass yield and body organs of 64­d old Sasso chicks are presented Table (15). It was found that feeding suboptimum CP and suboptimum CP with ME levels did not significantly affect percentage of dressing, front, hind, abdominal fat, liver, pancreas, spleen and cecum length. However, low CP diet significantly decreased intestines length as relative to live 77 BW, while decreasing CP with ME levels, yield similar values to the above mentioned groups. This decrease in intestines length could not be explained yet, however, may be correlated with decreasing feed intake (Table 8). Similarly, Olomu and Offiong (1980) and Abd­Elsamee (2002) found that dietary CP level did not significantly affect carcass yield of broiler chicks. El­Nagger et al. (1997), Attia et al. (1998 and 2003c) found that dietary CP and ME levels did not significantly affect carcass yield, internal organs of native hybrid chicks. Similarly, Attia et al. (2001) reported that intermediate decrease in CP and ME levels did not significantly affect dressed carcass, front and hind parts, pancreas and abdominal fat leaf, whereas significantly decreased liver percent. However, El Medany and El­Afif (2002) found that decreasing dietary CP level decreased carcass yield, giblets and increased abdominal fat of 21 d old chicks, however, the effect was diminished after feeding optimal CP level during the growing period. On the other hand, Ismail et al. (2006) found that dietary ME level and source did not significantly carcass yield of Japanese quail chicks. Venäläinen et al. (2006) found that dietary ME of 2868 kcal ME/kg significantly increased carcass weight, length, width and weight of bones compared to 2629 kcal ME/kg diet. It could be concluded that decreasing dietary CP and CP with ME level for Sasso chicks from one­d old to 64 d of age by ~1 and 100 kcal ME had no adverse effects on carcass yield and body organs. 4.10.2 Effect of type of phytase: Results displayed in Table (15) showed the effect of type of phytase on dressed carcass, front and hind parts and body organs of 64­ d old Sasso chickens. Results indicated that type of phytase had no significant effect on dressed carcass, front and hind parts and body organs. However, type of phytase significantly increased abdominal fat similarly by 47.0 and 58.3% compared to the positive control. The significant increase in abdominal fat could be attributed to the increase in energy availability (Kies et al., 2001 and Attia et al. 2001). It was found that phytase increased digestibility of DM and CF, which could reflected in increasing ME (Table 14).
78 Table 15. Relative weight of carcass characteristics and body organs of 64 d old Sasso chickens as affected by type of phytase and/or suboptimum‐ protein level or suboptimum‐protein and energy level Treatments Dressing % Front% Positive control 70.9 38.8 Low‐protein 68.4 Low‐Protein‐low energy SEM Hind% Abdominal fat% Liver% Pancreas % Spleen Intestinal length % Cecum length%
31.7 1.93 2.40 0.220 0.165 9.48 a 0.876 37.8 30.1 2.18 2.10 0.200 0.171 8.18 b 0.938 69.7 37.9 31.6 2.28 2.17 0.230 0.162 8.73 ab 0.939 0.794 0.382 0.705 0.249 0.096 0.013 0.012 0.286 0.037 NS NS NS NS NS NS NS 0.005 NS No phytase 70.0 38.6 30.9 1.68 b 2.40 0.220 0.165 9.32 0.911 Natuphos 67.9 37.1 31.0 2.47 a 2.07 0.230 0.174 8.65 0.963 Phyzyme 69.6 38.0 31.1 2.66 a 2.17 0.200 0.165 8.99 0.924 SEM 0.794 0.382 0.705 0.249 0.096 0.013 0.012 0.286 0.037 NS NS NS 0.02 NS NS NS NS NS % Main effect of diet P Value Main effect of type of phytase P Value 79 Interaction between phytase and diet Positive control 70.9 38.8 31.7 1.93 b 2.40 0.220 0.165 9.48 0.875 Low‐protein× No phytase 68.6 38.2 29.2 1.68 b 1.92 0.212 0.169 7.55 0.989 Low‐protein× Natuphos 67.1 37.3 30.5 2.02 b 2.29 0.206 0.147 7.96 0.938 Low‐protein× Phyzyme 69.4 37.9 30.6 2.84 ab 2.08 0.179 0.197 9.02 0.885 Low‐protein‐low energy× No phytase 70.6 38.7 31.7 1.44 b 2.05 0.249 0.154 7.91 0.868 Low‐protein‐low energy ×Natuphos 68.6 37.0 31.5 3.30 a 2.06 0.245 0.182 9.32 0.987 Low‐protein‐low energy ×Phyzyme 69.9 38.1 32.0 2.10 ab 2.05 0.194 0.150 8.92 0.962 SEM 1.20 0.584 1.07 0.379 0.147 0.020 0.018 0.489 0.056 NS NS NS 0.03 NS NS NS NS NS
P Value a‐b means within a column under the same treatment with different superscripts are significantly different. NS, not significant 80 The lack of significant effect of phytase on dressing, breast, thigh + legs and pancreas are in harmony with broilers studies reported by Qota et al. (2002) and El­ Medany and El­Afifi (2002) and with ducks by Attia (2003a;b and Attia et al., 2003c). In addition, Dosoky (2003) found that phytase as an independent variable had no significant effect on drawn, liver, gizzard, heart, pancreas and testis of Japanese quail. On the other hand, Pillai et al (2006) reported that E­Coli phytase­6 supplementation to P­ inadequate diet improved carcass yield of broiler chicks. In conclusion, type of phytase did not significantly affect carcass yield and body organs of Sasso chicks fed Ca and P adequate diets; however, there was significant increase in abdominal fat, suggesting an increase in energy availability that may be due to the increase in saturated fat and starch digestibility (Ravindran et al., 2000 and Kies et al., 2001). 4.10.3 Interaction between phytase type and diet: Data for the interaction between type of phytase and diet on carcass yield and body organs are displayed in Table (15). The results showed that percentage of dressed carcass, front and hind parts and body organs such as liver, pancreas, spleen and length of the intestines and length of cecum and intestine relative weight were not significantly affected by the interaction between type of phytase and diet. This indicated that the responses to the type of phytase and diet are independent variable. However, there was a significant increase in the abdominal fat when Natuphos was added to low protein with energy diet (Table 15). It could be concluded that there was no significant interaction between type of phytase and diet on percentage of, dressed carcass, front and hind parts and body organs such as liver, pancreas, spleen and length of the intestines and cecum. 4.11 Tibia characteristics: 4.11.1 Effect of dietary suboptimum CP and protein with energy levels: Data for the effect of feeding suboptimum CP and protein with energy level on Tibia characteristics of 64­d old Sasso chicks are presented in Table (16). It was found that feeding suboptimum CP and suboptimum CP with ME levels did not significantly affect length (mm), diameter (mm), weight (g) , ash (%), Ca (%) and P (%) of tibia compared to the positive control. In this respect , EL Medany and El­ Afifi (2002) found that reducing CP decreased tibia width, tibia breaking strength, and increased tibia weight, however, tibia length and tibia weight were not significantly affected at the end of the growing period. Along the same lime, Driver et al. (2005) found that protein level in broiler diets had no effect on tibia ash, which is similar to the present findings. Venäläinen et al. (2006) found that tibia ash, Ca, and P contents in broilers given diets with low ME (2629 kcal /kg diet) were greater than those given higher ME (2868 kcal /kg diet), and dietary ME had no effect on tibia breaking strength. However, Leterrier et al. (1998) found that tibia ash was not affected by feeding high (3181kcal /kg diet) and low (2299 kcal/kg diet) energy diet, which is similar to the present findings, Williams et al. (2000) showed that the cortical bone of modern fast­growth selected broilers was less well mineralized and had more porous than that of a slow­growing control strain, showing strain differences in bone mineralization and/or phosphorus tolerance. On the other hand, Zanini and Sazzad (1999) found that the low ME (2801. /kg diet) significantly, increased Ca and P in the bones compared to the high ME (3000kcal /kg diet).
66 It could be concluded that decreasing protein and protein with energy level in the diet for Sasso chicks during 1­64 d of age by ~1 and 100 kcal ME, respectively had no adverse effects on tibia characteristics and mineralization. 4.11.2 Effect of type of phytase: Results displayed in Tables (16) showed the effect of type of phytase on tibia length (mm), diameter (mm), weight (g), ash(%), Ca(%), and P (%) of 64­ d old Sasso chickens. Results indicated that type of phytase had no significant effect on all tibia characteristics and mineralization (Table 16). Piva et al. (1994) observed that tibia weight was lower (P<0.05) with 500 U of high activity phytase or low activity phytase than with 2000 U of high activity phytase or low activity phytase diets (­8.1 and ­11%, respectively). Tibia length was 4.3% greater with 1000 and 2000 U of low activity phytase diets and 4.5% with 1000 and 2000 U of high activity phytase diets than with the control diet (P<0.05). This indicates that tibia characteristics were significantly affected by type and level of phytase. Similar to the present findings, Akyurek et al. (2005) found that phytase­6 (Ronozyme) did not significantly affect DM, crude ash, toe Ca and phosphorus of broiler chicks. The lack of significant effect of type of phytase on tibia characteristics and mineralization may be, however, due to feeding adequate Ca and NPP levels (Tables 1, 2 and 3). Recent results by Venäläinen et al. (2006) indicated that tibia breaking strength was not significantly affected by dietary P level, and the response to phytase was plateau with a concentration of dietary available phosphorus from 0.41 to 0.45%. In the literature, the effect of phytase on toe and tibia ash and mineral contents are apparent (Attia et al., 2003; Augspurger et al., 2003; Augspurger and Baker, 2004), with the effect of E. coli phytase was stronger than fungal phytase­3 (Augspurger and Baker, 2004). However, Jendza et al. (2006) and Pillai et al. (2006) found that type of phytase did not affect tibia ash. Veum et al. (2006) showed no significant difference between E. coli phytase and P. Lycii phytase at 500 U in bone breaking strength and ash weight, and the apparent absorption (g/d and %) of P, Ca, and Mg , Zn, Fe, or Cu. Valaja et al. (2000) and Payne et al. (2005) found similar results.
67 Table 16. Tibia characteristics (%) and mineralization of 64 d old Sasso chickens as affected by type of phytase and/or suboptimum‐ protein level or suboptimum‐protein and energy level Treatments Tibia length mm Tibia Weight g Tibia diameter mm Tibia Tibia Ash% Ca, Positive control 110 7.59 11.7 44.7 20.3 10.2 Low‐protein 110 8.01 11.4 44.7 20.6 10.2 Low‐Protein‐low energy 109 8.06 11.5 44.9 20.8 10.4 SEM 1.40 0.440 0.30 0.260 0.200 0.110 NS NS NS NS NS NS No phytase 109 7.68 11.2 44.4 20.3 10.1 Natuphos 110 8.32 11.5 44.9 20.8 10.3 Phyzyme 111 7.98 11.8 45.2 20.9 10.4 SEM 1.4 0.44 0.30 0.26 0.20 0.11 P Value NS NS NS NS NS NS 110 7.59 11.7 44.8 20.3 10.2
% Tibia Phosphor u% Main effect of diet P Value Main effect of type of phytase Interaction between phytase and diet Positive control 68 Low‐protein× No phytase 108 7.52 10.6 44.5 20.4 10.1 Low‐protein× Natuphos 112 8.65 11.9 44.7 20.5 10.1 Low‐protein× Phyzyme 111 7.87 11.7 45.0 20.8 10.3 Low‐protein‐low energy× No phytase 109 7.92 11.4 44.1 20.2 10.1 Low‐protein‐low energy × Natuphos 108 7.99 11.2 45.2 21.2 10.5 Low‐protein‐low energy × Phyzyme 111 8.10 11.9 45.4 20.9 10.5 SEM 2.20 0.66 0.50 0.41 0.31 0.16 NS NS NS NS NS NS P Value NS, not significant In conclusion, type of phytase did not significantly affect tibia characteristics and mineralization of 64­ d old Sasso chicks fed diet containing reducing level of protein and protein with energy and adequate Ca and P levels. 4.11.3 Interaction between phytase type and diet: Data for the interaction between type of phytase and diet on tibia characteristics and mineralization of 64­ d old Sasso chick's s are shown in Table (16). The results showed that the interaction between type of phytase and diet had no significant effect on all tibia length (mm), diameter(mm), weight(g), ash(%), Ca(%) and P (%) (Table 16). This means that the responses to the type of phytase and diet are independent variable. In the literature, there was significant interaction between phytase and dietary phytic acid, revealing that phytase improved toe ash by greater extent at the high concentration of phytic acid and in the low NPP (Cabhug et al., 1999). Similarly, Zanini and Sazzad (1999) reported that there were strong interactions between phytase addition and dietary AME regarding tibia ash and P, with the phytase­3 producing higher ash content with the higher AME diet and a lower P content with the lower AME diet. However, Venäläinen et al. (2006) found no significant interaction between ME level and NPP on tibia characteristics and mineralization. Rodehutscord and Pfeffer. (2006) reported that a plateau in P­ utilization with an increase in phytase supplementation was achieved in study two, but not in study one, and the enzyme was more efficient in study two than study one at low rates of addition. They concluded that the efficacy of a microbial phytase varies even under similar condition, that may be due to differences in intrinsic phytase activity. It could be concluded that there was no significant interaction between type of phytase and diet on tibia characteristics and mineralization of 64­ d old Sasso chicks fed diet containing reducing level of protein and protein with energy and adequate Ca and P levels. 4.12. Chemical composition of muscle:
69 4.12.1 Effect of dietary suboptimum CP and protein with energy levels: Data for the effect of feeding suboptimum CP and protein with energy level on chemical composition of muscle of 64­d old Sasso chicks are presented in Table (17). It was found that decreasing protein level alone and protein with energy level had no significant effect on percentage DM, CP, EE and ash of meat. These results are in consistent with those observed by Olomu and Offiong (1980), El‐Nagger et al. (1997) and Abd‐Elsamee (2002) who found that dietary protein level did not significantly affect chemical composition of meat of broiler chicks. In addition, Attia et al. (2001) found that decreasing protein and energy level in broiler diets did not significantly affect DM, CP and EE of broiler meat. Shaldam (2003) found similar results with new improved local strains. On the other hand, Ismail et al (2006) found that feeding high energy diet (2900 Kcal ME/kg diet)decreased protein of Japanese quail meat, while increased DM of muscle compared to low ME level (2700 Kcal ME/kg diet). It could be concluded that suboptimum decrease in protein and energy levels did not significantly affect chemical composi on of meat of 64‐ d old Sasso chicks. 4.12.2 Effect of type of phytase: Results displayed in Table (17) showed the effect of type of phytase on chemical composition of muscle tissue of 64‐d old Sasso chickens. Results indicated that type of phytase had no significant influence on DM, CP, EE and ash of meat. The lack of significance of type of phytase on chemical composition of muscle tissue is in general agreement with the results reported by Attia et al. (2001), Qota et al. (2002), El‐Medany and El‐Afifi (2002), A a (2003a;b), Attia et al. (2003 c) and Ismail et al. (2006). They concluded that phytase supplementations to broilers, ducks , Japanese quail and native local strain diets did not significantly affect chemical composition of muscle tissue. In conclusion, type of phytase did not significantly influence chemical composition of muscle of 64­ d old Sasso chicks. 4.12.3 Interaction between type of phytase and diet: Results displayed in Table (17) showed the effect of type of phytase on chemical composition of muscle tissue of 64­d old Sasso chickens. The results indicated that there was no significant interaction between type of phytase and diet on percentage dry matter, crude protein, ether extract and crude ash of muscle tissue of 64­d old Sasso chicks. Table 17. Chemical composi on, % of muscle of 64 d old Sasso chickens as affected by type of phytase and/or suboptimum‐ protein level or suboptimum‐protein with energy level Treatments Dry matter % Main effect of diet
70 CP % EE % Ash % Positive control 27.0 75.1 18.9 4.87 Low‐protein 27.2 74.7 19.1 4.99 Low‐Protein‐low energy 26.9 74.8 18.9 4.97 SEM 0.378 0.275 0.289 0.131 NS NS NS NS No phytase 26.7 74.7 19.0 5.00 Natuphos 27.3 74.7 18.9 5.00 Phyzyme 27.3 75.1 19.0 4.86 SEM 0.378 0.275 0.289 0.131 NS NS NS NS Positive control 27.0 75.1 18.9 4.87 Low‐protein× No phytase 26.5 74.5 19.4 4.92 Low‐protein× Natuphos 27.3 74.8 18.9 5.02 Low‐protein× Phyzyme 27.8 74.9 19.0 5.03 Low‐protein‐low energy× No phytase 26.6 74.4 18.7 5.22 Low‐protein‐low energy × Natuphos 27.3 74.6 18.9 4.98 Low‐protein‐low energy × Phyzyme 26.9 75.3 19.0 4.70 SEM 0.577 0.420 0.442 0.199 NS NS NS NS P Value Main effect of type of phytase P Value Interaction between phytase and diet P Value NS, not significant. These results are coincided with, those of Attia (2003a; b) and Sadaka (2005) who observed that percentages of DM, crude protein, ether extract and ash of ducks meat were not significantly affected by the interaction between methionine level and phytase supplementation. Moreover, Ismail et al. (2006) whfound that percentage DM, CP, EE and ash of muscle tissue of Japanese quail showed no significant effect of the interaction between source or level of dietary energy and phytase. Similar results were reported with
71 pigs by Shelton et al. (2003) who indicated that phytase addition to diet containing different ME levels did not significantly affect DM, CP, fat and ash acceleration, showing that phytase had limited non­significant influence on energy availability in phosphorus inadequate diets for growing pigs. In conclusion, there were no significant differences in chemical composition of muscle tissue of Sasso chicks due to the interaction between type of phytase and diet containing suboptimum levels of protein and protein with energy and adequate levels of Ca and phosphorus. 4.13 Physical characteristics of meat: 4.13.1 Effect of dietary suboptimum CP and protein with energy level: Data for the effect of feeding suboptimum CP and protein with energy level on physical characteristics of meat of 64­d old Sasso chicks are shown (Table 18). The results indicated that decreasing CP level alone and CP with ME level had no significant effect on pH, color, WHC and tenderness of meat of 64 d old Sasso chicks. This coincided with the lack of significance of CP and ME here in chemical composition of muscle (Table 18). The lack of significance in chemical composition of muscle and their physical characteristics is expected and could be attributed to the use of dietary suboptimum CP and ME, thus there were small changes in the intake of C:P ratio e.g. 15.39, 16.22 and 15.69 of group fed the control, subnormal CP and CP with ME diets. These results are in consistent with those observed by El­Nagger et al. (1997) and Attia et al. (2004) who found that dietary CP and ME levels level did not significantly affect pH, color, WHC and tenderness of meat broiler and hybrid chicks. In addition, Attia et al. (2001) found that decreasing protein and energy levels in broiler diets did not significantly affect pH, color, WHC and tenderness of meat. Shaldam (2003) found that pH, color, WHC and tenderness of meat of new improved local strains were not significantly affected by dietary CP levels. Aggoor et al (2006) found that high ME level (2900 kcal ME/kg diet) significantly decreased WHC while increased meat color intensity compared to low ME diet (2700 kcal ME/kg diet).
72 Table 18. Physical characteris cs of muscle of 64 d old Sasso chickens as affected by type of phytase and/or suboptimum‐ protein level or suboptimum‐protein and energy level Treatments pH Color WHC Tenderness Main effect of diet Positive control 6.71 0.270 5.82 2.98 Low‐protein 7.00 0.277 5.77 2.91 Low‐Protein‐low energy 6.76 0.263 5.82 2.88 SEM 0.032 0.105 0.062 0.058 NS NS NS NS No phytase 6.71 0.262 5.82 2.91 Natuphos 6.71 0.273 5.84 2.84 Phyzyme 6.77 0.268 5.74 2.98 SEM 0.032 0.105 0.060 0.058 NS NS NS NS
P Value Main effect of type of phytase P Value 73 Interaction between phytase and diet Positive control 6.71 0.270 5.82 2.98 Low‐protein× No phytase 6.68 0.265 5.71 2.86 Low‐protein× Natuphos 6.64 0.280 5.78 2.86 Low‐protein× Phyzyme 6.77 0.268 5.80 3.02 Low‐protein‐low energy× No phytase 6.75 0.253 5.92 2.88 Low‐protein‐low energy × Natuphos 6.77 0.266 5.88 2.81 Low‐protein‐low energy × Phyzyme 6.76 0.268 5.66 2.94 SEM 0.049 0.016 0.095 0.088 NS NS NS NS P Value NS, not significant. It could be concluded that suboptimal protein and energy level did not significantly affect physical characteristics of muscle of 64­ d old Sasso chicks. 4.13.2 Effect of type of phytase: Results displayed in Table (18) showed the effect of type of phytase on physical characteristics of muscle of 64­d old Sasso chicks. The results indicated that type of phytase had no significant impact on pH, color, tenderness and WHC of muscle of Sasso chicks compared to the positive control. These results are coincided with the lack of significance of enzymes on chemical composition of muscle. The lack of significance of type of phytase on physical characteristics of muscle are in general agreement with the results reported by Attia et al. (2001), Attia (2003a;b), Attia et al. (2003c and2006b), Qota et al. (2002), Sadaka (2005) and Ismail et al. (2006). They concluded that addition of phytase­3 or phytase­6 in broilers, ducks and Japanese quail diets had no significant effect on physical characteristics of muscle tissue. In conclusion, enzyme supplementations did not significantly influence physical characteristics of muscle of 64d old Sasso chicks. 4.13.3 Interaction between type of phytase and diet: Data for the interaction between type of phytase and diet on physical characteristics of meat are presented in Table (18). It was found that pH, color intensity, tenderness and WHC of muscle tissues of Sasso chickens were not significantly affected by the interaction between type of phytase and diet containing suboptimum level of protein and protein with energy. Attia (2003b) , Ismail et al. (2006b) and Sadaka (2005) reported similar findings. These authors observed that physical characteristics of ducks and Japanese quail meat and new developed strains of local chicks were not affected by the interaction between methionine, lysine level or source
74 and level of dietary energy and fungal phytase­3 or ­6 supplementation. Furthermore, our results coincided with the lack of significance of the interaction in chemical composition of muscle tissues (Table 17). In conclusion, pH, color intensity, tenderness and WHC of muscle of Sasso chicks were not significantly influenced by the interaction between type of phytase and diet containing suboptimal levels of dietary protein and protein with energy. 4.14 Plasma constituents: 4.14.1 Effect of dietary suboptimum CP and protein with energy level: Data for the effect of feeding diet containing suboptimal CP and CP with ME level on plasma constituents of 64­d old of Sasso chicks are shown in Tables (19 and 20). It was found that low CP diet without or with low ME level had no significant effect on plasma total protein, globulin, total lipids, cholesterol (Table 19) and liver enzymes AST and ALT, and plasma Ca, P and alkaline phosphtase (Table 20). On the other hand, decreasing CP and CP with ME level caused unexplained significant increase in plasma albumin. The lack of significant effect of protein and protein with energy on the most of the plasma constituents indicated that CP and ME levels were adequate and did not adversely affect plasma constituents. These results are in agreement with the results of El­Nagger et al. (1997), Attia et al. (2001) Attia (2003c) and Aggoor et al. (2006). Similary, Attia et al. (2003c) concluded that decreasing CP level by 2% had no significant effect on plasma Ca and P of local hybrid chicks. It could be concluded that reducing protein level and protein with energy level had no significant effect on plasma constituents of Sasso chicks, which may be due to the use of narrow decrease in dietary CP and ME. 4.14.2 Effect of type of phytase: Results displayed in Tables (19 and 20) exhibited the effect of type of phytase on plasma total protein, albumen, globulin, total lipids, cholesterol (Table 19) and liver enzymes AST and ALT, Ca, P and alkaline phosphtase (Table 20) of 64­d old Sasso chickens. Results indicated that type of phytase had no significant impact on plasma total protein, albumen, globulin, total lipids, alkaline phosphtase and liver enzymes AST. The lack of significant Table 19. Plasma cons tuents of 64 d old Sasso chickens as affected by type of phytase and/or suboptimum‐ protein level or suboptimum‐protein and energy level Treatments Total protein Albumin Globulin Total Lipids Cholesterol 6.91 111.8
Main effect of diet Positive control 4.15 75 1.11 b 3.00 Low‐protein 3.91 1.53 a 2.39 7.00 115.4 Low‐Protein‐low energy 4.00 1.47 a 2.63 6.87 105.9 SEM 0.133 0.042 0.130 52.1 4.42 NS 0.0001 NS NS NS No phytase 4.14 1.38 2.74 6.94 124.0 a Natuphos 3.85 1.45 2.45 6.96 100.3 b Phyzyme 3.87 1.42 2.46 6.90 101.7 b SEM 0.133 0.042 0.130 52.1 4.42 NS NS NS NS 0.0001 Positive control 4.15 1.10 3.00 6.91 111.8 Low‐protein× No phytase 4.04 1.51 2.54 7.12 140.6 Low‐protein× Natuphos 4.08 1.59 2.49 6.98 106.2 Low‐protein× Phyzyme 3.61 1.47 2.14 6.90 99.5 Low‐protein‐low energy× No phytase 4.24 1.53 2.71 6.77 119.6 Low‐protein‐low energy × Natuphos 3.63 1.47 2.43 6.93 94.4 Low‐protein‐low energy × Phyzyme 4.14 1.38 2.76 6.89 103.9 SEM 38.7 0.059 0.212 80.1 6.70 NS NS NS NS NS P Value Main effect of type of phytase P Value Interaction between phytase and diet P Value a‐b , means within a column under the same treatment with different superscripts are significantly different. NS, not significant. effect of phytases enzymes on plasma constituents under investigations indicated that phytase did not affect biochemical constituents of blood plasma and liver enzymes e.g. AST. These results are in general agreement with the results reported by Attia et al. (2001), Qota et al. (2002), Attia (2003a;b) Attia et al. (2003c) and El­Ghamry et al. (2005). They concluded that phytase supplementation to broilers, ducks and local hybrid chickens diets, respectively had no significant effect on plasma constituents.
76 In accordance with the present findings, Piva et al. (1994) reported that there were no differences between control and experimental diets in Ca, Na, Zn, P, urea, total proteins, and globulin and aspartate aminotransferase in blood. However, Viveros et al. (2002) found that phytase­3 (Natuphos) supplementation to low­P diets increased plasma P level (P<0.01), and serum AST activity, reduced plasma Ca, and Mg, and reduced serum ALT, lactate dehydrogenase and alkaline phosphtase. Table20. Biochemical constituents of blood plasma of 64 d old Sasso chickens as affected by type of phytase and/or suboptimum‐ protein level or suboptimum‐protein and energy level Treatments Calcium Phosphorus Alkaline phosphtase AST ALT Main effect of diet Positive control 10.6 6.29 51.5 11.0 5.58 Low‐protein 11.2 6.52 52.2 10.9 5.53 Low‐Protein‐low energy 11.3 6.52 51.2 10.8 5.41 SEM 0.230 0.040 5.37 0.178 0.120 NS NS NS NS NS P Value Main effect of type of phytase No phytase 10.3 b 6.21 b 52.3 11.1 5.45 b Natuphos 11.6 a 6.71 a 51.3 10.7 5.19 b Phyzyme 11.9 a 6.69 a 51.1 10.6 5.85 a SEM 0.230 0.040 5.37 0.178 0.120 P Value 0.0001 0.0001 NS NS 0.002 Positive control 10.6 6.29 51.5 11.0 5.58 Low‐protein× No phytase 10.3 6.14 52.6 11.0 5.35 Low‐protein× Natuphos 11.5 6.72 53.0 10.9 5.25 Low‐protein× Phyzyme 11.8 6.69 51.1 10.7 5.99 Low‐protein‐low energy× No phytase 10.0 6.20 52.7 11.3 5.42
Interaction between phytase and diet 77 Low‐protein‐low energy × Natuphos 11.8 6.70 49.6 10.7 5.12 Low‐protein‐low energy × Phyzyme 12.1 6.68 51.2 10.4 5.71 SEM 0.346 0.062 8.20 0.270 0.170 NS NS NS NS NS P Value a‐b means within a column under the same treatment with different superscripts are significantly different. NS , not significant. It is therefore, concluded that the effect of phytase on plasma constituents depends on available phosphorus level. On the other hand, both Natuphos and E­Coli phytase significantly decreased plasma cholesterol similarly (Table 19), while Phyzyme only significantly increased plasma ALT (Table 20). Similarly, Qota et al. (2002) , Attia et al. (2003a; b) and Ismail et al. (2006) found that phytase additions to the broiler, ducklings and Japanese quail diets did not significantly affect plasma protein, lipids, and cholesterol. In addition, Rodehutscord and Peffer .(2006) found that fungal phytase­6 derived from Peniophora lycii did not affect concentration of AST, while ALT was significantly increased of ducklings, which is in harmony with the present findings with Sasso chicks when E. coli phytase was supplemented. It was found that plasma Ca and P were significantly increased due to phytase supplementation, with similar effects of both types of phytase on Ca and P adequate diet (Table 20). This indicated the hydrolysis of P and Ca of phytic acid molecule (Kies et al., 2001; A a et al., 2003c). However, (Roberson and Edwards, 1994) showed that phytase had no significant effect on plasma Ca. However, El‐Deeb et al. (2000) indicated that phytase‐supplemented birds showed comparable serum inorganic phosphorus concentration to those of the positive control. Plasma phosphorus was decreased by phytase addition only when the higher phosphorus level was fed Roberson and Edwards (1994). Similarly, Attia et al. (2001) found that phytase supplementation numerically increased plasma P of all the experimental diets; however, significant increase was only shown of group fed suboptimum CP with ME diet. Along the same line, Perney et al. (1993) reported that phytase supplementation to a maize‐soybean meal diet containing less phosphorus than the recommended level by NRC (1994) increased toe and tibia ash and plasma P of broiler chicks. Similarly, Rodehutscord and Pfeffer (2006) found that blood serum phosphate, but not Ca was significantly increased by phytase supplementation to ducklings diets. In conclusion, phytase supplementations to adequate Ca and P diets containing reduced level of CP and ME significantly increased plasma Ca and phosphorus, while reduced plasma cholesterol level of 64‐ d old Sasso chicks. 4.14.3 Interaction between type of phytase and diet: Data for the interaction between type of phytase and diet on plasma total protein, albumen, globulin, total lipids and cholesterol and liver enzymes AST and ALT, plasma
78 Ca, P and alkaline phosphtase of 64­d old Sasso chickens are presented in Tables (19 and 20). It was found that plasma total protein, albumen, globulin, total lipids, cholesterol and serum liver enzymes AST and ALT of 64­d old Sasso chickens were not significantly affected by the interaction between type of phytase and diet. Similarly, Attia (2003a; b), Sadaka (2005) and Ismail et al. (2006) observed that plasma constituents were not significantly affected by the interaction between fungal phytase­3 and methionine level and fungal phytase­6 or source and level of dietary phytase and ME supplementation. In conclusion, there was no significant interaction between type of phytase and diet on plasma constituents of 64­d old Sasso chicks. 4.15. Economical efficiency: 4.15.1 Effect of dietary suboptimum CP and protein with energy levels: Data for the effect of feeding diet containing suboptimal CP and suboptimal CP with ME levels on economical efficiency study of 64­d old of Sasso chicks are shown in Table (21). Feeding cost and total costs were found to be decreased due to feeding low protein and low protein with energy diet, with significantly the effect was linear due to decreased both nutrients. On the other hand, total revenue, net revenue, economical efficiency and production index were not significantly affected due to decreased protein level alone or with energy level (Table 21). These results coulirm the possibility of applying such program in feeding Sasso chicks without significant loss in economical efficiency. 4.15.2 Effect of type of phytase: Results displayed in Table (21) showed the main effect of type phytase on economical efficiency of Sasso chickens during 1­64 d of age. It was found that type of phytase significantly decreased feeding cost and total cost with the effect of phytase­6 was more efficient than phytase­3. Meanwhile, total revenue, net revenue, economical efficiency and production index were not significantly affected by type of phytase. 4.15.3 Interaction between type of phytase and diet: Data for the interaction between type of phytase and diet on economical efficiency study are shown in Table (21). The results indicated that phytase decreased feeding cost and total cost of Sasso diets with the effect of phytase­6 was more efficient than phytase­3 in only low CP and ME diet. Obviously, decreasing CP with ME was more effective for decreasing feeding costs than decreasing CP alone (Table 21). On the other hand, there was no significant interaction between type of phytase and dietary nutrients on total revenue, net revenue, economical efficiency, and production index. However, the best economic efficiency was recorded by group fed low CP with ME
79 diet followed by that diet supplemented with phyzyme and Natuphos. On the other hand, the best production index was recorded by the positive control followed by the unsupplemented low CP diet, and low CP with ME diet. This indicates that both parameters give different results. These results are in agreement with the results of Shakmak (2003) with Japanese quail and Attia et al. (2001) and Attia (2003a; b) with broiler chicks and ducklings. In conclusion,to obtain the best economical efficiency, Sasso chickens may be fed diet containing low CP with low ME diet.
80 Table21. Economic efficiency and produc on index of 64 d old Sasso chickens as affected by type of phytase and/or suboptimum‐ protein level or suboptimal‐protein and energy level Treatments Feeding cost, LE Total cost, LE Total revenue, Net revenue, LE LE Economic efficiency,% Production index,% Main effect of diet Positive control 6.38 a 9.38 a 14.1 4.7 49.8 169.3 Low‐protein 6.01 b 9.01 b 13.2 4.2 46.3 158.2 Low‐Protein‐low energy 5.77 c 8.77 c 13.2 4.5 50.9 156.7 SEM 0.018 0.018 0.155 0.155 1.72 3.74 P Value 0.0001 0.0001 NS NS NS NS No phytase 6.13 a 9.13 a 13.7 4.6 50.0 163.8 Natuphos 5.91 b 8.90 b 13.1 4.2 47.4 155.3 Phyzyme 5.76 c 8.76 c 13.0 4.2 48.2 156.0 SEM 0.018 0.018 0.155 0.155 1.72 3.74 P Value 0.0001 0.0001 NS NS NS NS
Main effect of type of phytase 81 Interaction between phytase and diet Positive control 6.38 a 9.38 a 14.1 4.68 49.8 169.3 Low‐protein× No phytase 6.20 b 9.20 b 13.6 4.42 48.0 161.5 Low‐protein× Natuphos 6.00 c 9.00 c 13.0 4.04 45.0 153.9 Low‐protein× Phyzyme 5.84 d 8.84 d 12.9 4.07 46.1 154.7 Low‐protein‐low energy× No phytase 5.81 d 8.81 d 13.4 4.60 52.2 160.7 Low‐protein‐low energy × Natuphos 5.82 d 8.82 d 13.4 4.40 50.0 156.8 Low‐protein‐low energy × Phyzyme 5.67 e 8.67 e 13.1 4.38 50.5 157.3 SEM 0.028 0.028 0.236 0.236 2.71 5.71 P Value 0.004 0.004 NS NS NS NS a‐b means within a column under the same treatment with different superscripts are significantly different. NS, not significant.
82 5. Summary and Conclusion The nutrient requirements of Sasso chicks are not well established in the literature, and efforts are needed to establish the CP and ME requirements of this type of chickens in the absence and the presence of phytases using the current guide of phytase for CP and ME utilization to improve nutrient utilization, to decrease feeding costs and environmental pollution and improve economic efficiency. Therefore, the present study was run to study the effect of two types of phytase on the performance of Sasso chicks fed the suboptimal CP, and CP with ME compared to the control diet. The experiment was carried out at private sector poultry farm from the period from June to August, 2005, whereas slaughter test, biochemical constituents of blood, and digestibility traits were completed at Animal and Poultry production Department, Faculty of Agriculture. Damanhour, Alexandria University. Moreover, meat quality and tibia analyses were determined at Sakha Animal Production Research Laboratoies. Productive performance, digestibility of nutrients, carcass quality, plasma constituents and economic evaluation were studied during 1‐64 d of age. Each diet was fed to five replicates of 12 chicks each . The diets used in this experiments were : 1. Posi ve control diet containing 21.2% CP with 2947 kcal ME in the starter diet (1‐35 d of age), 19.6% CP with 3023 kcal ME in the grower diet (36‐56 d of age) and 18.0% CP with 3100 kcal ME in the finisher diet (57‐64 d of age). 2‐ Suboptimum CP diet containing less 1% CP in the starter, grower and finisher diets than the control group and without phytase supplementations. 3‐ Suboptimum CP diet containing less 1% CP in the starter, grower and finisher diets than the control group supplemented with 500 U of fungal phytase‐3 (Natuphos)/kg diet. 4‐ Suboptimum CP diet containing less 1% CP in the starter, grower and finisher diets than the control group supplemented with 500 U of E. coli phytase‐6 (Phyzyme)/kg diet. 5‐ Suboptimum CP with ME diet containing less 1% CP and 100 kcal ME/kg diet in the starter, grower and finisher diets without phytase supplementations. 6‐ Suboptimum CP with ME diet supplemented with 500 U of fungal phytase‐3 (Natuphos)/kg diet. 7‐ Suboptimum CP with ME diet supplemented with 500 U of E. coli phytase‐6 (Phyzyme)/kg diet. The results could be summarized as the following: 1. Dietary treatments had no significant effect on growth of chicks during starter period. Whereas, decreasing CP level without or with fungal phytase and suboptimum CP and ME level
83 without or with both sources of phytase decreased significantly, BWG from 36 to 56 d of age compared to the positive control, while differences were insignificant between the suboptimum CP diet supplemented with microbial phytase and other dietary treatments. 2. Suboptimum CP level without or with fungal phytase and suboptimum CP and ME level with the bacterial phytase increased BWG significantly from 57 to 64 d of age compared to the positive control. Meanwhile, other dietary treatments increased BWG; however, the differences were not significant compared to the positive control. Decreasing dietary CP and CP with ME, and/or source of phytase supplementations did not significantly affect the total BWG and final BW. 4. Irrespective of phytase addition, feeding suboptimum CP diet and suboptimum CP with ME decreased the BWG significantly from 36 to 56 d of age, while induced the contrary trend from 57 to 64 d of age. Meanwhile, there were no significant differences in BWG from one to 35 and from one to 64 d of age. 5. Irrespec ve of dietary CP and ME, supplementa on of either fungal or bacterial phytase decreased significantly the BWG from 36 to 56 d of age, while the contrary trend was observed due to supplementation of the fungal phytase compared to the bacterial phytase and the control group from 57 to 64 d of age. Meanwhile, difference was insignificant from one‐d old to 35 and from one‐d old to 64 d of age. 6. Dietary treatments decreased significantly feed consumption from one ‐d old to 35, 36 to 56 and from one to 64 d of age compared to the posi ve control, except that group fed the low CP which showed no significant difference from the posi ve control from 36 to 56 d of age. Bacterial phytase supplementation for the suboptimum CP or low CP with ME decreased significantly feed consump on compared to the other dietary treatments from 36 to 56 d of age. 7. Suboptimum CP diet or low CP with ME supplemented with bacterial phytase exhibited the lowest feed consumption for the complete experimental period compared to the positive control, other groups showed less severe feed consumption. 8. For the most of the experimental period, suboptimum CP level or CP with ME significantly decreased feed consumption. Meanwhile, source of phytase had a significant negative effect on feed consumption during all the experimental period, with the bacterial phytase showed more severe effect than the fungal phytase from one to 35, 57 to 64 and one to 64 d of age, regardless of dietary CP and ME levels. 10. Dietary treatments significantly impaired FCR from 36 to 56 d of age while the worst FCR was shown of group fed suboptimum CP supplemented with fungal phytase compared to the posi ve control. Meanwhile, the contrary trend was shown from 56 to 63 d of age.
84 11. Suboptimum CP and ME levels and/or phytase supplementation had no significant effect on FCR for one‐d old to 35 d of age and from one‐d old to 64 d of age, however, the posi ve control exhibited the best. 12. Conversion of CP and ME were significantly improved due to feeding suboptimum CP and CP with ME diets. Meanwhile, source of phytase and its interaction with the diet did not affect CP and ME conversion for the complete experimental period. 13. Mortality was within the normal range, however, group fed low CP, and low CP with ME showed higher number of dead birds. 14. Dietary treatments had no significant effect on apparent digestibility of CP, CF, EE, and DM, apparent ash retention, fecal, excreta and metabolic nitrogen. Both source of phytases similarly improved significantly digestibility of DM, CF, CP and apparent ash retention when compared to phytase unsupplemented‐group. Meanwhile, decreasing CP and CP with ME significantly decreased fecal nitrogen by 6.7% compared to the positive control resulted in less environmental pollution. 15. Decreasing level of CP only resulted in significant deceased in intestine percentage compared to the positive control. 16. Low CP with ME diet supplemented with fungal and bacterial phytase increased significantly abdominal fat compared to the positive control. Whereas, difference between the low CP diet and low CP and ME supplemented with bacterial phytase was insignificant. 17. Dietary treatments had no significant effect on chemical composition of muscle, and physical characteristics of muscle and morphological and mineralization of tibia compared to the positive control. 18. Fungal phytase increased significantly plasma Ca and P compared to the unsupplemented control, however, differences between the bacterial and fungal phytase were insignificant. Bacterial phytase increased serum ALT and both sources did not affect serum AST. On the other hand, both sources of phytase decreased significantly serum cholesterol. 19. Plasma albumin was significantly increased due to decreasing CP level and CP with ME compared to positive control. On the other hand, both sources of phytase significantly decreased plasma cholesterol similarly compared with unsupplemented control. 20. The positive control group exhibited the best production index, while the best economic efficiency was recorded by the low CP with ME diet. In conclusion, Sasso chicks could be fed diet containing 20.2% CP with 2850 kcal ME supplemented with 500 FTU of fungal phytase from 1‐35 d of age, and 19.6% CP with 3092 kcal ME/kg diet from 36‐56 d of age, and 17% CP with 3023 kcal ME/kg diet from 57‐64 d of age for
85 the best‐FCR. However, from economic point of view the control diet resulted in the best production index and low CP with ME diet recorded the best economic efficiency.
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‫‪ ‬ﻻ‪ ‬ﺑﺎ‪ ‬ﺱ ‪ ‬ﺑﻪ‪ ‬ﻣﻦ‪ ‬ﺍﻟﻤﺴﺘﻬﻠﻜﻴﻦ‪ ‬ﻓﻲ‪ ‬ﻟﺤﻮﻡ‪ ‬ﺗﻠﻚ‪ ‬ﺍﻟﺴﻼﻻﺕ‪ ٬‬ﻭ‪ ‬ﻣﻊ‪ ‬ﺑﺬﻟﻚ‪ ‬ﻓﺎﻥ‪ ‬ﺗﻐﺬﻳﺔ‪ ‬ﻫﺬﺓ‪ ‬ﺍﻷﻧ‪ ‬ﻮﺍﻉ‪ ‬ﻣﺎﺯﺍﻟ‪ ‬ﺖ‪ ‬ﻓ‪ ‬ﻲ‪ ‬ﺍﻟﻤﻬ‪ ‬ﺪ‪ ‬ﻭ‪ ‬ﺗﻔﺘﻘ‪ ‬ﺮ‪ ‬ﺍﻟﻤﺮﺍﺟ‪ ‬ﻊ‬
‫‪ ‬ﺇﻟﻲ‪ ‬ﺍﻟﻤﻌﻠﻮﻣﺎﺕ‪ ‬ﺍﻟﺨﺎﺻﺔ‪ ‬ﺑﺎﺣﺘﻴﺎﺟﺎﺗﻬﺎ‪ ‬ﺍﻟﻐﺬﺍﺋﻴﺔ‪ ‬ﺳﻮﺍء‪ ‬ﻣﻦ‪ ‬ﺣﻴﺚ‪ ‬ﻣﺴ‪ ‬ﺘﻮﻳﺎﺕ‪ ‬ﺍﻟﺒ‪ ‬ﺮﻭﺗﻴﻦ‪ ‬ﻭ‪ ‬ﺍﻟﻄﺎﻗ‪ ‬ﺔ‪ ‬ﺃﻭ‪ ‬ﺍﻟﻌﻨﺎﺻ‪ ‬ﺮ‪ ‬ﺍﻟﻤﻌﺪﻧﻴ‪ ‬ﺔ‪ ‬ﺍﻻﺧ‪ ‬ﺮﻱ‪ ‬ﻭ‬
‫‪ ‬ﺗﻌﺘﻤﺪ‪ ‬ﺗﻐﺬﻳﺔ‪ ‬ﺗﻠﻚ‪ ‬ﺍﻷﻧﻮﺍﻉ‪ ‬ﺗﺤﺖ‪ ‬ﻇﺮﻭﻑ‪ ‬ﺍﻹﻧﺘﺎﺝ‪ ‬ﺍﻟﺘﺠﺎﺭﻱ‪ ‬ﻋﻠﻲ‪ ‬ﺍﻻﺟﺘﻬﺎﺩﺍﺕ‪ ‬ﻣﺴﺘﻌﻴﻨ‪ ‬ﺔ‪ ‬ﻓﻲ‪ ‬ﺍﻏﻠﺐ‪ ‬ﺍﻷﻭﻗﺎﺕ‪ ‬ﺑﺘﻐﺬﻳﺔ‪ ‬ﺍﻷﻧ‪ ‬ﻮﺍﻉ ‪ ‬ﺳ‪ ‬ﺮﻳﻌﺔ‬
‫‪ ‬ﻣﻤﺎ‪ ‬ﻳﻬﺪﺭ‪ ‬ﺍﻟﻌﻨﺎﺻﺮ‪ ‬ﺍﻟﻐﺬﺍﺋﻴﺔ‪ ‬ﻭ‪ ‬ﺑﺎﻟﺘﺒﻌﻴﺔ‪ ‬ﺗ‪ ‬ﺰﺩﺍﺩ‪ ‬ﺗﻜﻠﻔ‪ ‬ﺔ‪ ‬ﺍﻟﺘﻐﺬﻳ‪ ‬ﺔ‪ ‬ﻭﺳ‪ ‬ﻌﺮ‪ ‬ﺍﻟﻤﻨ‪ ‬ﺘﺞ‪ ‬ﺍﻟﻨﻬ‪ ‬ﺎﺋﻲ‪ ‬ﻓﻀ‪ ‬ﻼ ‪(Broilers) ‬ﺍﻟﻨﻤﻮ‪ ‬ﻣﻦ‪ ‬ﺩﺟﺎﺝ‪ ‬ﺍﻟﻠﺤﻢ‬
‫‪ ‬ﻋﻦ ‪ ‬ﺯﻳﺎﺩﺓ‪ ‬ﺍﻟﺘﻠﻮﺙ‪ ‬ﺍﻟﺒﻴﺌﻲ‪ ‬ﻧﺘﻴﺠ‪ ‬ﺔ‪ ‬ﺍﻟﻔﻘﺪ‪ ‬ﻓﻲ‪ ‬ﺍﻟﻌﻨﺎﺻﺮ‪ ‬ﺍﻟﻐﺬﺍﺋﻴﺔ‪ ‬ﻭ‪ ‬ﻣﻦ‪ ‬ﻫﺬﺍ‪ ‬ﺍﻟﻤﻨﻄﻠﻖ‪ ‬ﻓﻘﺪ‪ ‬ﺃﺟﺮﻳﺖ‪ ‬ﻫﺬﻩ‪ ‬ﺍﻟﺘﺠﺮﺑﺔ‪ ‬ﺑﻬﺪﻑ‪ ‬ﺍﻟﻮﻗﻮ‪ ‬ﻑ ‪ ‬ﻋﻠ‪ ‬ﻰ‬
‫‪ ‬ﺗﺄﺛﻴﺮ‪ ‬ﻣﺴﺘﻮﻱ‪ ‬ﺍﻟﺒﺮﻭﺗﻴﻦ‪ ‬ﻭ‪ ‬ﺍﻟﻄﺎﻗﺔ‪ ‬ﻋﻠﻲ‪ ‬ﺃﺩﺍء ‪ ‬ﺳﻼﻟﺔ‪ ‬ﺍﻟﺴﺎﺳﻮ‪ ‬ﻭ‪ ‬ﺗﺄﺛﻴﺮ‪ ‬ﻧﻮﻋﻴ‪ ‬ﻦ‪ ‬ﻣﻦ‪ ‬ﺍﻟﻔﻴﺘﻴﺰ‪ ‬ﺍﻟﻤﻴﻜﺮﻭﺑ‪ ‬ﻲ‪ ‬ﻋﻠ‪ ‬ﻲ‪ ‬ﺗﺤﺴ‪ ‬ﻴﻦ‪ ‬ﺍﻻﺳ‪ ‬ﺘﻔﺎﺩﺓ‪ ‬ﻣ‪ ‬ﻦ‬
‫‪ ‬ﺍﻟﺒﺮﻭﺗﻴﻦ‪ ‬ﻭ‪ ‬ﺍﻟﻄﺎﻗﺔ‪ ‬ﻓﻲ‪ ‬ﻋﻼﺋﻖ‪ ‬ﺗﺤﺘﻮﻱ‪ ‬ﻣﺴﺘﻮﻳﺎﺕ‪ ‬ﻛﺎﻓﻴﺔ‪ ‬ﻣﻦ‪ ‬ﺍﻟﻜﺎﻟﺴﻴﻮﻡ‪ ‬ﻭ‪ ‬ﺍﻟﻔﻮﺳﻔﻮﺭ‪. ‬‬
‫‪ ‬ﻭ‪ ‬ﺍﺟﺮﻱ‪ ‬ﺍﻟﺒﺤﺚ‪ ‬ﻓﻲ‪ ‬ﻣﺰﺭﻋﺔ‪ ‬ﺧﺎﺻﺔ‪ ‬ﺑﻜﻔﺮ‪ ‬ﺍﻟﺪﻭﺍﺭ ‪ – ‬ﻣﺤﺎﻓﻈﺔ‪ ‬ﺍﻟﺒﺤﻴﺮﺓ‪ ‬ﻓﻲ‪ ‬ﺍﻟﻔﺘﺮﺓ‪ ‬ﻣﻦ ‪ ‬ﻳﻮﻧﻴﻮ‪ ‬ﺇﻟﻰ‪ ‬ﺃﻏﺴﻄﺲ ‪ 2005 ‬ﺑﻴﻨﻤﺎ‪ ‬ﺃﺟﺮﻳﺖ‬
‫‪ ‬ﺗﺠ‪ ‬ﺎﺭﺏ‪ ‬ﺍﻟ‪ ‬ﺬﺑﺢ‪ ‬ﻭ‪ ‬ﺗﺤﻠ‪ ‬ﻴﻼﺕ‪ ‬ﺍﻟ‪ ‬ﺪﻡ‪ ‬ﺑﻜﻠﻴ‪ ‬ﺔ‪ ‬ﺍﻟﺰﺭﺍﻋ‪ ‬ﺔ‪ ‬ﺑ‪ ‬ﺪﻣﻨﻬﻮﺭ ‪ – ‬ﺟﺎﻣﻌ‪ ‬ﺔ‪ ‬ﺍﻹﺳ‪ ‬ﻜﻨﺪﺭﻳﺔ‪ ‬ﻭﺍﺳ‪ ‬ﺘﻜﻤﻠﺖ‪ ‬ﺍﻟﺘﺤﻠ‪ ‬ﻴﻼﺕ‪ ‬ﺍﻟﻜﻴﻤﺎﻭﻳ‪ ‬ﺔ‪ ‬ﻭﺧ‪ ‬ﻮﺍﺹ‬
‫‪ ‬ﺍﻟﻠﺤ‪ ‬ﻮﻡ‪ ‬ﺑﻤﻌﺎﻣ‪ ‬ﻞ‪ ‬ﺑﺤ‪ ‬ﻮﺙ‪ ‬ﺍﻹﻧﺘ‪ ‬ﺎﺝ‪ ‬ﺍﻟﺤﻴ‪ ‬ﻮﺍﻧﻲ‪ ‬ﺑﺴ‪ ‬ﺨﺎ‪ ‬ﻣﺤﺎﻓﻈ‪ ‬ﺔ‪ ‬ﻛﻔ‪ ‬ﺮ‪ ‬ﺍﻟﺸ‪ ‬ﻴﺦ‪ . ‬ﻭ‪ ‬ﺫﻟ‪ ‬ﻚ‪ ‬ﺑﻬ‪ ‬ﺪﻑ‪ ‬ﺩﺭﺍﺳ‪ ‬ﺔ‪ ‬ﺗ‪ ‬ﺄﺛﻴﺮ‪ ‬ﺇﺿ‪ ‬ﺎﻓﺔ‪ ‬ﺇﻧ‪ ‬ﺰﻳﻢ‪ ‬ﺍﻟﻔﻴﺘﻨ‪ ‬ﺰ‬
‫‪ ( ‬ﺇﻟ‪ ‬ﻰ‪ ‬ﻋﻼﺋ‪ ‬ﻖ‪ ‬ﺍﻟﺒ‪ ‬ﺎﺩﻱء‪ ‬ﻭﺍﻟﻨ‪ ‬ﺎﻣﻲ‪ ‬ﻭﺍﻟﻨ‪ ‬ﺎﻫﻲ‪ ‬ﻭﺍﻟﻤﻨﺨﻔﻀ‪ ‬ﺔ‪ ‬ﻓ‪ ‬ﻲ‪ ‬ﻧﺴ‪ ‬ﺒﺔ‪ ‬ﺍﻟﺒ‪ ‬ﺮﻭﺗﻴﻦ ‪ ( Natuphos ‬ﺃﻭﺍﻟﻔﻄ‪ ‬ﺮﻱ ‪ Phyzyme ) ‬ﺍﻟﺒﻜﺘﻴﺮﻱ‪) ‬‬
‫‪ ‬ﺍﻟﺨﺎﻡ‪ ‬ﺑﻤﻘﺪﺍﺭ ‪ % 1 ‬ﻭﺍﻟﻄﺎﻗﺔ‪ ‬ﺍﻟﻤﻤﺜﻠﺔ‪ ‬ﺑﻤﻘﺪﺍﺭ ‪ 100 ‬ﻛﻴﻠﻮ‪ ‬ﻛﺎﻟﻮﺭﻱ‪ ‬ﻟﺪﺟﺎﺝ‪ ‬ﺍﻟﻠﺤﻢ‪ ‬ﻣﻦ‪ ‬ﺳﻼﻟﺔ‪ ‬ﺍﻟﺴﺎﺳﻮ‪ ‬ﻋﻠﻲ‪ ‬ﺑﻌﺾ‪ ‬ﺍﻟﺼ‪ ‬ﻔﺎﺕ‪ ‬ﺍﻹﻧﺘﺎﺟﻴ‪ ‬ﺔ‬
‫‪ ‬ﻭ‪ ‬ﺟﻮﺩﺓ‪ ‬ﺍﻟﻠﺤﻮﻡ‪ ‬ﻭ‪ ‬ﺗﺤﺴﻴﻦ‪ ‬ﺍﻻﺳﺘﻔﺎﺩﺓ‪ ‬ﻣﻦ‪ ‬ﺍﻟﺒﺮﻭﺗﻴﻦ‪ ‬ﺍﻟﺨﺎﻡ‪ ‬ﻭﺍﻟﻄﺎﻗﺔ‪ ‬ﺍﻟﻤﻤﺜﻠﺔ‪ . ‬ﻭ‪ ‬ﻗﺪ‪ ‬ﺗﻢ‪ ‬ﺍﺳﺘﺨﺪﺍﻡ ‪ 420 ‬ﻛﺘﻜﻮﺕ‪ ‬ﻣﻦ‪ ‬ﻋﻤﺮ‪ ‬ﻳ‪ ‬ﻮﻡ‪ ‬ﻭﺣﺘ‪ ‬ﻰ‬
‫‪ ‬ﻋﻤﺮ ‪ 64 ‬ﻳﻮﻡ‪ ‬ﻭﺯﻋﺖ‪ ‬ﻋﺸﻮﺍﺋﻴﺎ‪ ‬ﻋﻠﻰ‪ ‬ﺳﺒﻊ ‪ ( 7 ) ‬ﻣﻌﺎﻣﻼﺕ‪ ‬ﺗﺠﺮﻳﺒﻴﺔ‪ ‬ﺑﻜﻞ‪ ‬ﻣﻌﺎﻣﻠﺔ ‪ 5 ‬ﻣﻜﺮﺭﺍﺕ‪ ‬ﻛﻞ‪ ‬ﻣﻜ‪ ‬ﺮﺭﺓ ‪ ‬ﺑﻬ‪ ‬ﺎ ‪ 12 ‬ﻛﺘﻜ‪ ‬ﻮﺕ‪ ‬ﻏﻴ‪ ‬ﺮ‬
‫‪ ‬ﻣﺠﻨﺲ‪ ‬ﻋﻤﺮ‪ ‬ﻳﻮﻡ‪ ٬‬ﻭ‪ ‬ﻏﺬﻳﺖ‪ ‬ﺍﻟﻄﻴﻮﺭ‪ ‬ﻋﻠﻰ‪ ‬ﻋﻠﻴﻘﺔ‪ ‬ﺍﻟﺒﺎﺩﻱ‪ ‬ﻓ‪ ‬ﻲ‪ ‬ﺍﻟﻔﺘ‪ ‬ﺮﺓ‪ ‬ﻣ‪ ‬ﻦ‪ ‬ﻋﻤ‪ ‬ﺮ ‪ 1 ‬ﺣﺘ‪ ‬ﻰ ‪ 35 ‬ﻳ‪ ‬ﻮﻡ‪ ‬ﻭﻋﻠﻴﻘ‪ ‬ﻪ‪ ‬ﺍﻟﻨ‪ ‬ﺎﻣﻲ‪ ‬ﻓ‪ ‬ﻲ‪ ‬ﺍﻟﻔﺘ‪ ‬ﺮﺓ‪ ‬ﻣ‪ ‬ﻦ‬
‫‪ ‬ﻋﻤﺮ ‪ 35 ‬ﻳﻮﻡ‪ ‬ﺣﺘﻰ ‪ ‬ﻋﻤﺮ‪ 56 ‬ﻭﻋﻠﻰ‪ ‬ﻋﻠﻴﻘﻪ‪ ‬ﺍﻟﻨﺎﻫﻲ‪ ‬ﻓﻲ‪ ‬ﺍﻟﻔﺘﺮﺓ‪ ‬ﻣﻦ‪ ‬ﻋﻤﺮ ‪ 56 ‬ﺣﺘﻰ ‪ 64 ‬ﻳﻮﻡ‪. ‬‬
‫‪ ‬ﻭﻭﺯﻋﺖ‪ ‬ﺍﻟﻤﻌﺎﻣﻼﺕ‪ ‬ﻛﻤﺎ‪ ‬ﻳﻠﻲ‪­ : ‬‬
‫‪ ‬ﺍﻷﻭﻟﻰ‪ ­ : ‬ﻏ‪ ‬ﺬﻳﺖ‪ ‬ﻋﻠ‪ ‬ﻰ‪ ‬ﻋﻠﻴﻘ‪ ‬ﻪ‪ ‬ﺍﻟﻜﻨﺘ‪ ‬ﺮﻭﻝ‪ ‬ﻭﺍ‪ ‬ﻣﻤﺜﻠ‪ ‬ﺔ‪ ‬ﻓ‪ ‬ﻲ ‪ ‬ﻋﻠ‪ ‬ﻰ ‪ % 21.2 ‬ﺑ‪ ‬ﺮﻭﺗﻴﻦ‪ ‬ﻣ‪ ‬ﻊ ‪ 2947 ‬ﻛﻴﻠ‪ ‬ﻮ‪ ‬ﻛ‪ ‬ﺎﻟﻮﺭﻱ‪ ‬ﻃﺎﻗ‪ ‬ﺔ‪ ‬ﻣﻤﺜﻠ‪ ‬ﺔ‪ ‬ﻓ‪ ‬ﻲ‪ ‬ﻣﺮﺣﻠ‪ ‬ﺔ‬
‫‪ ‬ﺍﻟﺒﺎﺩﻱ‪ % 19.6 ٬‬ﺑﺮﻭﺗﻴﻦ‪ ‬ﻣﻊ ‪ 3092 ‬ﻛﻴﻠﻮ‪ ‬ﻛﺎﻟﻮﺭﻱ‪ ‬ﻃﺎﻗ‪ ‬ﺔ‪ ‬ﻣﻤﺜﻠ‪ ‬ﺔ‪ ‬ﻓ‪ ‬ﻲ‪ ‬ﻣﺮﺣﻠ‪ ‬ﺔ‪ ‬ﺍﻟﻨ‪ ‬ﺎﻣﻲ‪ ٬‬ﻭ ‪ % 18 ‬ﺑ‪ ‬ﺮﻭﺗﻴﻦ‪ ‬ﻣ‪ ‬ﻊ ‪ 3023 ‬ﻛﻴﻠ‪ ‬ﻮ ‪ ‬ﻛ‪ ‬ﺎﻟﻮﺭﻱ‬
‫‪ ‬ﻃﺎﻗﺔ ‪ ‬ﻣﻤﺜﻠﺔ‪ ‬ﻓﻲ‪ ‬ﻣﺮﺣﻠﺔ‪ ‬ﺍﻟﻨﺎﻫ‪ ‬ﻲ ‪ ‬ﻋﻠﻰ‪ ‬ﺍﻟﺘﺮﺗﻴﺐ‪ ) ‬ﻛﻨﺘﺮﻭﻝ‪ ‬ﺇﻳﺠﺎﺑﻲ‪.( ‬‬
‫‪ ‬ﺍﻟﺜﺎﻧﻴ‪ ‬ﺔ‪ ­ : ‬ﻏ‪ ‬ﺬﻳﺖ‪ ‬ﻋﻠ‪ ‬ﻰ‪ ‬ﻋﻼﺋ‪ ‬ﻖ‪ ‬ﺍﻟﺒﺎﺩﻱ‪٬‬ﺍﻟﻨ‪ ‬ﺎﻣﻲ‪ ‬ﻭﺍﻟﻨ‪ ‬ﺎﻫﻲ‪ ‬ﻣﻨﺨﻔﻀ‪ ‬ﺔ‪ ‬ﻓ‪ ‬ﻲ‪ ‬ﻧﺴ‪ ‬ﺒﺔ‪ ‬ﺍﻟﺒ‪ ‬ﺮﻭﺗﻴﻦ‪ ‬ﺍﻟﺨ‪ ‬ﺎﻡ‪ ‬ﺑﻤﻘ‪ ‬ﺪﺍﺭ ‪ % 1 ‬ﻭﺫﻟ‪ ‬ﻚ‪ ‬ﻋﻨ‪ ‬ﺪ‪ ‬ﻣﻘﺎﺭﻧﺘﻬ‪ ‬ﺎ‬
‫‪ ‬ﺑﻤﺠﻤﻮﻋﺔ‪ ‬ﺍﻟﻜﻨﺘﺮﻭﻝ‪ ‬ﺍﻻﻳﺠﺎﺑﻲ‪ ‬ﻭﺑﺪﻭﻥ‪ ‬ﺇﺿﺎﻓﺔ‪ ‬ﺇﻧﺰﻳﻢ‪ ‬ﺍﻟﻔﻴﺘﺰ‪. ‬‬
‫‪ ‬ﺍﻟﺜﺎﻟﺜ‪ ‬ﺔ‪ ­ : ‬ﻏ‪ ‬ﺬﻳﺖ‪ ‬ﻋﻠ‪ ‬ﻰ‪ ‬ﻋﻼﺋ‪ ‬ﻖ‪ ‬ﺍﻟﺒ‪ ‬ﺎﺩﻱ‪ ٬‬ﺍﻟﻨ‪ ‬ﺎﻣﻲ‪ ‬ﻭﺍﻟﻨ‪ ‬ﺎﻫﻲ‪ ‬ﻣﻨﺨﻔﻀ‪ ‬ﺔ‪ ‬ﻓ‪ ‬ﻲ‪ ‬ﻧﺴ‪ ‬ﺒﺔ‪ ‬ﺍﻟﺒ‪ ‬ﺮﻭﺗﻴﻦ‪ ‬ﺍﻟﺨ‪ ‬ﺎﻡ‪ ‬ﺑﻤﻘ‪ ‬ﺪﺍﺭ ‪ % 1 ‬ﻭﺫﻟ‪ ‬ﻚ‪ ‬ﻋﻨ‪ ‬ﺪ‪ ‬ﻣﻘﺎﺭﻧﺘﻬ‪ ‬ﺎ‬
‫‪ ‬ﺑﻤﺠﻤﻮﻋﺔ‪ ‬ﺍﻟﻜﻨﺘﺮﻭﻝ‪ ‬ﺍﻻﻳﺠﺎﺑﻲ‪ ‬ﻣﻊ‪ ‬ﺇﺿﺎﻓﺔ‪ ‬ﺍﻟﻔﻴﺘﺰ‪ ‬ﺍﻟﻔﻄﺮﻱ‪ ‬ﺑﻤﻌﺪﻝ ‪ 500 ‬ﻭﺣﺪﺓ‪ / ‬ﻛﺠﻢ‪ ‬ﻋﻠﻒ‪. ‬‬
‫‪ ‬ﺍﻟﺮﺍﺑﻌ‪ ‬ﺔ‪ ­ : ‬ﻏ‪ ‬ﺬﻳﺖ‪ ‬ﻋﻠ‪ ‬ﻰ‪ ‬ﻋﻼﺋ‪ ‬ﻖ‪ ‬ﺍﻟﺒﺎﺩﻱ‪٬‬ﺍﻟﻨ‪ ‬ﺎﻣﻲ‪ ‬ﻭﺍﻟﻨ‪ ‬ﺎﻫﻲ‪ ‬ﻣﻨﺨﻔﻀ‪ ‬ﺔ‪ ‬ﻓ‪ ‬ﻲ‪ ‬ﻧﺴ‪ ‬ﺒﺔ‪ ‬ﺍﻟﺒ‪ ‬ﺮﻭﺗﻴﻦ‪ ‬ﺍﻟﺨ‪ ‬ﺎﻡ‪ ‬ﺑﻤﻘ‪ ‬ﺪﺍﺭ ‪ % 1 ‬ﻭﺫﻟ‪ ‬ﻚ‪ ‬ﻋﻨ‪ ‬ﺪ‪ ‬ﻣﻘﺎﺭﻧﺘﻬ‪ ‬ﺎ‬
‫‪ ‬ﺑﻤﺠﻤﻮﻋﺔ‪ ‬ﺍﻟﻜﻨﺘﺮﻭﻝ‪ ‬ﺍﻻﻳﺠﺎﺑﻲ‪ ‬ﻣﻊ‪ ‬ﺇﺿﺎﻓﺔ‪ ‬ﺍﻟﻔﻴﺘﺰ‪ ‬ﺍﻟﺒﻜﺘﻴﺮﻱ‪ ‬ﺑﻤﻌﺪﻝ ‪ 500 ‬ﻭﺣﺪﺓ‪ / ‬ﻛﺠﻢ‪ ‬ﻋﻠﻒ‪. ‬‬
‫‪ ‬ﺍﻟﺨﺎﻣﺴﺔ‪ ­ : ‬ﻏﺬﻳﺖ‪ ‬ﻋﻠﻰ‪ ‬ﻋﻼﺋﻖ‪ ‬ﺍﻟﺒﺎﺩﻱ‪ ٬‬ﺍﻟﻨﺎﻣﻲ‪ ‬ﻭﺍﻟﻨﺎﻫﻲ‪ ‬ﻣﻨﺨﻔﻀﺔ‪ ‬ﻓﻲ‪ ‬ﻧﺴﺒﺔ‪ ‬ﺍﻟﺒ‪ ‬ﺮﻭﺗﻴﻦ‪ ‬ﺍﻟﺨ‪ ‬ﺎﻡ‪ ‬ﺑﻤﻘ‪ ‬ﺪﺍﺭ ‪ % 1 ‬ﻭ‪ ‬ﻣﻨﺨﻔﻀ‪ ‬ﺔ‪ ‬ﻓ‪ ‬ﻲ‪ ‬ﺍﻟﻄﺎﻗ‪ ‬ﺔ‬
‫‪ ‬ﺍﻟﻤﻤﺜﻠﺔ‪ ‬ﺑﻤﻘﺪﺍﺭ ‪ 100 ‬ﻛﻴﻠﻮ‪ ‬ﻛﺎﻟﻮﺭﻱ‪ / ‬ﻛﺠﻢ‪ ‬ﻋﻠﻒ‪ ‬ﻭﺫﻟﻚ‪ ‬ﻋﻨﺪ‪ ‬ﻣﻘﺎﺭﻧﺘﻬﺎ‪ ‬ﺑﻤﺠﻤﻮﻋﺔ‪ ‬ﺍﻟﻜﻨﺘﺮﻭﻝ‪ ‬ﺍﻻﻳﺠﺎﺑﻲ‪ ‬ﻭﺑﺪﻭﻥ‪ ‬ﺇﺿﺎﻓﺔ‪ ‬ﺍﻟﻔﻴﺘﻴﺰ‪. ‬‬
‫‪ ‬ﺍﻟﺴﺎﺩﺳﺔ‪ ­ : ‬ﻏﺬﻳﺖ‪ ‬ﻋﻠﻰ‪ ‬ﻋﻼﺋﻖ‪ ‬ﺍﻟﺒﺎﺩﻱ‪ ٬‬ﺍﻟﻨﺎﻣﻲ‪ ‬ﻭﺍﻟﻨﺎﻫﻲ‪ ‬ﻣﻨﺨﻔﻀﺔ‪ ‬ﻓﻲ‪ ‬ﻧﺴﺒﺔ‪ ‬ﺍﻟﺒﺮﻭﺗﻴﻦ‪ ‬ﺍﻟﺨ‪ ‬ﺎﻡ‪ ‬ﺑﻤﻘ‪ ‬ﺪﺍﺭ ‪ % 1 ‬ﻭ‪ ‬ﻣﻨﺨﻔﻀ‪ ‬ﺔ‪ ‬ﻓ‪ ‬ﻲ‪ ‬ﺍﻟﻄﺎﻗ‪ ‬ﺔ‬
‫‪ ‬ﺍﻟﻤﻤﺜﻠﺔ‪ ‬ﺑﻤﻘﺪﺍﺭ ‪ 100 ‬ﻛﻴﻠﻮ‪ ‬ﻛﺎﻟﻮﺭﻱ‪ / ‬ﻛﺠﻢ‪ ‬ﻋﻠﻒ‪ ‬ﻭﺫﻟﻚ‪ ‬ﻋﻨﺪ‪ ‬ﻣﻘﺎﺭﻧﺘﻬﺎ‪ ‬ﺑﻤﺠﻤﻮﻋﺔ‪ ‬ﺍﻟﻜﻨﺘﺮﻭﻝ‪ ‬ﺍﻻﻳﺠﺎﺑﻲ‪ ‬ﻣﻊ‪ ‬ﺇﺿﺎﻓﺔ‪ ‬ﺍﻟﻔﻴﺘ‪ ‬ﺰ‪ ‬ﺍ‪ ‬ﻟﻔﻄ‪ ‬ﺮﻱ‪ ‬ﺑﻤﻌ‪ ‬ﺪﻝ‬
‫‪ 500 ‬ﻭﺣﺪﺓ‪ / ‬ﻛﺠﻢ‪ ‬ﻋﻠﻒ‪.‬‬
‫‪108 ‬‬
‫‪ ‬ﺍﻟﺴ‪ ‬ﺎﺑﻌﺔ‪ ­ : ‬ﻏ‪ ‬ﺬﻳﺖ‪ ‬ﻋﻠ‪ ‬ﻰ‪ ‬ﻋﻼﺋ‪ ‬ﻖ‪ ‬ﺍﻟﺒ‪ ‬ﺎﺩﻱ‪ ٬‬ﺍﻟﻨ‪ ‬ﺎﻣﻲ‪ ‬ﻭﺍﻟﻨ‪ ‬ﺎﻫﻲ‪ ‬ﻣﻨﺨﻔﻀ‪ ‬ﺔ‪ ‬ﻓ‪ ‬ﻲ‪ ‬ﻧﺴ‪ ‬ﺒﺔ‪ ‬ﺍﻟﺒ‪ ‬ﺮﻭﺗﻴﻦ‪ ‬ﺍﻟﺨ‪ ‬ﺎﻡ‪ ‬ﺑﻤﻘ‪ ‬ﺪﺍﺭ ‪ % 1 ‬ﻭ‪ ‬ﻣﻨﺨﻔﻀ‪ ‬ﺔ‪ ‬ﻓ‪ ‬ﻲ‪ ‬ﺍﻟﻄﺎﻗ‪ ‬ﺔ‬
‫‪ ‬ﺍﻟﻤﻤﺜﻠﺔ‪ ‬ﺑﻤﻘﺪﺍﺭ ‪ 100 ‬ﻛﻴﻠﻮ‪ ‬ﻛﺎﻟﻮﺭﻱ‪ / ‬ﻛﺠﻢ‪ ‬ﻋﻠﻒ‪ ‬ﻭﺫﻟﻚ‪ ‬ﻋﻨﺪ‪ ‬ﻣﻘﺎﺭﻧﺘﻬﺎ‪ ‬ﺑﻤﺠﻤﻮﻋﺔ‪ ‬ﺍﻟﻜﻨﺘﺮﻭﻝ‪ ‬ﺍﻻﻳﺠﺎﺑﻲ‪ ‬ﻣﻊ‪ ‬ﺇﺿﺎﻓﺔ‪ ‬ﺍﻟﻔﻴﺘﺰ‪ ‬ﺍﻟﺒﻜﺘﻴﺮﻱ‪ ‬ﺑﻤﻌ‪ ‬ﺪﻝ‬
‫‪ 500 ‬ﻭﺣﺪﺓ‪ / ‬ﻛﺠﻢ‪ ‬ﻋﻠﻒ‪. ‬‬
‫‪ ‬ﻭﻓﻲ‪ ‬ﻧﻬﺎﻳﺔ‪ ‬ﺍﻟﺘﺠﺮﺑﺔ‪ ‬ﺗﻢ‪ ‬ﺫﺑﺢ ‪ 10 ‬ﻃﻴﻮﺭ‪ ‬ﻣﻦ‪ ‬ﻛﻞ‪ ‬ﻣﻌﺎﻣﻠﺔ ‪ 5 ) ‬ﺇﻧﺎﺙ ‪ 5 + ‬ﺫﻛﻮﺭ‪ ( ‬ﺑﺈﺟﻤﺎﻟﻲ ‪ 70 ‬ﻃﺎﺋﺮ‪ ‬ﻟﺪﺭﺍﺳﺔ‪ ‬ﻣﻮﺍﺻﻔﺎﺕ‪ ‬ﺍﻟﺬﺑﻴﺤﺔ‪ ‬ﻭﻧﻮﻋﻴﺔ‬
‫‪ ‬ﻭﺟﻤﻌﺖ‪ ‬ﻋﺸ‪ ‬ﺮ‪ ‬ﻋﻴﻨ‪ ‬ﺎﺕ‪ ‬ﺩﻡ‪ ‬ﻟﺪﺭﺍﺳ‪ ‬ﺔ‪ ‬ﻣﻜﻮﻧ‪ ‬ﺎﺕ‪ ‬ﺍﻟ‪ ‬ﺪﻡ‪ ‬ﻣ‪ ‬ﻦ‪ ‬ﺍﻟﻔﻮﺳ‪ ‬ﻔﻮﺭ ‪ – ‬ﺍﻟﻜﺎﻟﺴ‪ ‬ﻴﻮﻡ‪ ‬ﻭ ‪ ‬ﺃﻧﺰﻳﻤ‪ ‬ﺎﺕ ‪ Tibia ‬ﺍﻟﻠﺤﻮﻡ‪ ‬ﻭﻣﻮﺍﺻﻔﺎﺕ‪ ‬ﻋﻈﻤﺔ ‪ ‬ﺍﻝ‬
‫‪ ‬ﻭﺗﻘﺪﻳﺮ‪ ‬ﺑﻌﺾ‪ ‬ﻣﻜﻮﻧﺎﺕ‪ ‬ﺑﻼﺯﻣﺎ‪ ‬ﺍﻟﺪﻡ‪ ‬ﺍﻟﺒﻴﻮﻛﻴﻤﺎﻭﻳﺔ‪ ‬ﻣﻦ‪ ‬ﺑﺮﻭﺗﻴﻦ‪ ٬‬ﺍﻟﺒﻴﻮﻣﻴﻦ‪ ٬‬ﺟﻠﻮﺑﻴﻮﻟﻴﻦ‪ ‬ﻭ‪ ‬ﺩﻫﻦ‪ ‬ﻭ‪ ‬ﻛﻠﺴﺘﺮﻭﻝ‪ . ‬ﻛﻤﺎ ‪ALP ٬ AST ٬ ALT ‬‬
‫‪ ‬ﺃﺟﺮﻳﺖ‪ ‬ﺗﺠﺮﺑﺔ‪ ‬ﻫﻀﻢ‪ ‬ﻓﻲ‪ ‬ﻧﻬﺎﻳﺔ‪ ‬ﺍﻟﺘﺠﺮﺑﺔ‪ ‬ﻟﺪﺭﺍﺳﺔ‪ ‬ﺃﺛﺮ‪ ‬ﺍﻟﻤﻌﺎﻣﻼﺕ‪ ‬ﺍﻟﺴﺎﺑﻘﺔ‪ ‬ﻋﻠﻰ‪ ‬ﻣﻌﺎﻣﻼﺕ‪ ‬ﻫﻀﻢ‪ ‬ﺍﻟﻌﻨﺎﺻﺮ‪ ‬ﺍﻟﻐﺬﺍﺋﻴﺔ‪. ‬‬
‫‪ ‬ﻭﻛﺎﻧﺖ‪ ‬ﺃﻫﻢ‪ ‬ﺍﻟﻨﺘﺎﺋﺞ‪ ‬ﺍﻟﻤﺘﺤﺼﻞ‪ ‬ﻋﻠﻴﻬﺎ‪ ‬ﻣﺎ‪ ‬ﻳﻠﻲ ‪: ‬‬
‫‪ ­ 1 ‬ﻟ‪ ‬ﻢ‪ ‬ﺗ‪ ‬ﻮﺛﺮ‪ ‬ﺍﻟﻤﻌ‪ ‬ﺎﻣﻼﺕ‪ ‬ﺍﻟﺘﺠﺮﺑﻴﺒ‪ ‬ﺔ‪ ‬ﺍﻟﻤﺨﺘﻠﻔ‪ ‬ﺔ‪ ‬ﻋﻠ‪ ‬ﻲ‪ ‬ﻣﻌ‪ ‬ﺪﻻﺕ‪ ‬ﺍﻟﻨﻤ‪ ‬ﻮ‪ ‬ﺧ‪ ‬ﻼﻝ‪ ‬ﻓﺘ‪ ‬ﺮﺓ‪ ‬ﺍﻟﺒ‪ ‬ﺎﺩﻱ‪ ٬‬ﺑﻴﻨﻤ‪ ‬ﺎ‪ ‬ﺃﺩﻯ‪ ‬ﺧﻔ‪ ‬ﺾ‪ ‬ﻣﺤﺘ‪ ‬ﻮﻱ‪ ‬ﺍﻟﻌﻠ‪ ‬ﻒ‪ ‬ﻣ‪ ‬ﻦ‬
‫‪ ‬ﺍﻟﺒ‪ ‬ﺮﻭﺗﻴﻦ‪ ‬ﺍﻟﺨ‪ ‬ﺎﻡ‪ ‬ﺑ‪ ‬ﺪﻭﻥ‪ ‬ﺃﻭ‪ ‬ﻣ‪ ‬ﻊ‪ ‬ﺇﺿ‪ ‬ﺎﻓﺔ‪ ‬ﺍﻟﻔﻴﺘ‪ ‬ﺰ‪ ‬ﺍﻟﻔﻄ‪ ‬ﺮﻱ‪ ‬ﺃﻭ‪ ‬ﺧﻔ‪ ‬ﺾ‪ ‬ﺍﻟﺒ‪ ‬ﺮﻭﺗﻴﻦ‪ ‬ﺍﻟﺨ‪ ‬ﺎﻡ‪ ‬ﻭﺍﻟﻄﺎﻗ‪ ‬ﺔ‪ ‬ﺍﻟﻤﻤﺜﻠ‪ ‬ﺔ‪ ‬ﺑ‪ ‬ﺪﻭﻥ‪ ‬ﺃﻭ‪ ‬ﻣ‪ ‬ﻊ‪ ‬ﺇﺿ‪ ‬ﺎﻓﺔ‪ ‬ﺍﻱ‪ ‬ﻣ‪ ‬ﻦ‬
‫‪ ‬ﺍﻻﻧﺰﻳﻤﻴﻦ‪ ‬ﺇﻟﻰ‪ ‬ﺍﻧﺨﻔﺎﺽ‪ ‬ﻣﻌﻨﻮﻱ‪ ‬ﻓﻲ‪ ‬ﺍﻟﺰﻳﺎﺩﺓ‪ ‬ﻓﻲ‪ ‬ﻭﺯﻥ‪ ‬ﺍﻟﺠﺴﻢ‪ ‬ﺧﻼﻝ‪ ‬ﺍﻟﻔﺘﺮﺓ‪ ‬ﻣﻦ ‪ 56 – 35 ‬ﻳﻮﻡ‪ ‬ﻣﻦ‪ ‬ﺍﻟﻌﻤﺮ‪ ‬ﻣﻘﺎﺭﻧﺔ‪ ‬ﺑﻤﺠﻤﻮﻋﺔ‪ ‬ﺍﻟﻜﻨﺘﺮﻭﻝ‬
‫‪ ‬ﺍﻹﻳﺠﺎﺑﻲ‪ ‬ﺑﻴﻨﻤﺎ‪ ‬ﻟﻢ‪ ‬ﺗﻜﻦ‪ ‬ﺍﻟﻔﺮﻭﻕ‪ ‬ﻣﻌﻨﻮﻳﺔ‪ ‬ﺑﻴﻦ‪ ‬ﻣﺠﻤﻮﻋﺔ‪ ‬ﺧﻔﺾ‪ ‬ﻣﺴﺘﻮﻱ‪ ‬ﺍﻟﺒﺮﻭﺗﻴﻦ‪ ‬ﺍﻟﺨﺎﻡ‪ ‬ﻣﻊ‪ ‬ﺇﺿﺎﻓﺔ‪ ‬ﺍﻟﻔﻴﺘﺰ‪ ‬ﺍﻟﺒﻜﺘﻴﺮﻱ‪ ‬ﻭ‪ ‬ﺑﺎﻗﻲ‪ ‬ﺍﻟﻤﻌ‪ ‬ﺎﻣﻼﺕ‬
‫‪ ‬ﺍﻟﺘﺠﺮﺑﻴﺒﺔ‪. ‬‬
‫‪ ­ 2 ‬ﺃﺩﻯ‪ ‬ﺧﻔﺾ‪ ‬ﻣﺤﺘﻮﻱ‪ ‬ﺍﻟﻌﻠﻒ‪ ‬ﻣﻦ‪ ‬ﺍﻟﺒﺮﻭﺗﻴﻦ‪ ‬ﺍﻟﺨﺎﻡ‪ ‬ﺑﺪﻭﻥ‪ ‬ﺃﻭ‪ ‬ﻣﻊ‪ ‬ﺇﺿﺎﻓﺔ‪ ‬ﺍﻧﺰﻳﻢ‪ ‬ﺍﻟﻔﻴﺘﺰ‪ ‬ﺍﻟﻔﻄﺮﻱ‪ ‬ﻭ‪ ‬ﺧﻔﺾ‪ ‬ﺍﻟﺒ‪ ‬ﺮﻭﺗﻴﻦ‪ ‬ﺍ‪ ‬ﻟﺨ‪ ‬ﺎﻡ‪ ‬ﻭﺍﻟﻄﺎﻗ‪ ‬ﺔ‬
‫‪ ‬ﺍﻟﻤﻤﺜﻠﺔ‪ ‬ﻣﻊ‪ ‬ﺇﺿﺎﻓﺔ‪ ‬ﺍﻟﻔﻴﺘﺰ‪ ‬ﺍﻟﺒﻜﺘﻴﺮﻱ‪ ‬ﺇﻟﻰ‪ ‬ﺗﺤﺴﻦ‪ ‬ﻣﻌﻨ‪ ‬ﻮﻱ‪ ‬ﻓ‪ ‬ﻲ‪ ‬ﺍﻟﺰﻳ‪ ‬ﺎﺩﺓ‪ ‬ﻓ‪ ‬ﻲ‪ ‬ﻭﺯﻥ‪ ‬ﺍﻟﺠﺴ‪ ‬ﻢ‪ ‬ﻓ‪ ‬ﻲ‪ ‬ﺍﻟﻔﺘ‪ ‬ﺮﺓ ‪ 64 – 56 ‬ﻳ‪ ‬ﻮﻡ‪ ‬ﻣ‪ ‬ﻦ‪ ‬ﺍﻟﻌﻤ‪ ‬ﺮ‪ ‬ﻣﻘﺎﺭﻧ‪ ‬ﺔ‬
‫‪ ‬ﺑﻤﺠﻤﻮﻋ‪ ‬ﺔ‪ ‬ﺍﻟﻜﻨﺘ‪ ‬ﺮﻭﻝ‪ ‬ﺍﻹﻳﺠ‪ ‬ﺎﺑﻲ‪ ‬ﺑﻴﻨﻤ‪ ‬ﺎ‪ ‬ﺃﺩﺕ‪ ‬ﺑ‪ ‬ﺎﻗﻲ‪ ‬ﺍﻟﻤﻌ‪ ‬ﺎﻣﻼﺕ‪ ‬ﺇﻟ‪ ‬ﻰ‪ ‬ﺗﺤﺴ‪ ‬ﻦ‪ ‬ﻓ‪ ‬ﻲ‪ ‬ﺍﻟﺰﻳ‪ ‬ﺎﺩﺓ‪ ‬ﻓ‪ ‬ﻲ‪ ‬ﻭﺯﻥ‪ ‬ﺍﻟﺠﺴ‪ ‬ﻢ‪ ‬ﻭﺇﻥ‪ ‬ﻟ‪ ‬ﻢ‪ ‬ﺗﻜ‪ ‬ﻦ‪ ‬ﺍﻟﺰﻳ‪ ‬ﺎﺩﺓ‪ ‬ﻣﻌﻨﻮﻳ‪ ‬ﺔً‬
‫‪ ‬ﻣﻘﺎﺭﻧﺔ‪ ‬ﺑﻤﺠﻤﻮﻋﺔ‪ ‬ﺍﻟﻜﻨﺘﺮﻭ‪ ‬ﻝ‪ ‬ﺍﻹﻳﺠﺎﺑﻲ‪ ‬ﺧﻼﻝ‪ ‬ﻫﺬﻩ‪ ‬ﺍﻟﻔﺘ‪ ‬ﺮﺓ‪ . ‬ﻫ‪ ‬ﺬﺍ‪ ‬ﻭﻟ‪ ‬ﻢ‪ ‬ﺗﻜ‪ ‬ﻦ‪ ‬ﻫﻨ‪ ‬ﺎﻙ‪ ‬ﺍﺧﺘﻼﻓ‪ ‬ﺎﺕ‪ ‬ﻣﻌﻨﻮﻳ‪ ‬ﺔ‪ ‬ﺑ‪ ‬ﻴﻦ‪ ‬ﺟﻤﻴ‪ ‬ﻊ‪ ‬ﺍﻟﻤﻌ‪ ‬ﺎﻣﻼﺕ‪ ‬ﺍﻟﺘﺠﺮﻳﺒﻴ‪ ‬ﺔ‬
‫‪ ‬ﺧﻼﻝ‪ ‬ﺍﻟﻔﺘﺮﺓ‪ ‬ﺍﻟﻜﻠﻴﺔ‪ ‬ﻟﻠﺘﺠﺮﺑﺔ‪ ‬ﻣﻦ ‪ 64 – 1 ‬ﻳﻮﻡ‪ ‬ﻣﻦ‪ ‬ﺍﻟﻌﻤﺮ‪. ‬‬
‫‪ ‬ﺑﻐﺾ‪ ‬ﺍﻟﻨﻈﺮ‪ ‬ﻋﻦ ‪ ‬ﺇﺿﺎﻓﺔ‪ ‬ﺍﻟﻔﻴﺘﻴﺰ‪ ‬ﺃﺩﻯ‪ ‬ﺧﻔﺾ‪ ‬ﻣﺤﺘﻮﻯ‪ ‬ﺍﻟﻌﻠ‪ ‬ﻒ‪ ‬ﻣ‪ ‬ﻦ‪ ‬ﺍﻟﺒ‪ ‬ﺮﻭﺗﻴﻦ‪ ‬ﺍﻟﺨ‪ ‬ﺎﻡ‪ ‬ﺃﻭ‪ ‬ﺍﻟﺒ‪ ‬ﺮﻭﺗﻴﻦ‪ ‬ﺍﻟﺨ‪ ‬ﺎﻡ‪ ‬ﻭﺍﻟﻄﺎﻗ‪ ‬ﺔ‪ ‬ﺍﻟﻤﻤﺜﻠ‪ ‬ﺔ‪ ‬ﺇﻟ‪ ‬ﻰ‬
‫‪­ 3 ‬‬
‫‪ ‬ﺍﻧﺨﻔﺎﺽ‪ ‬ﻣﻌﻨ‪ ‬ﻮﻱ‪ ‬ﻓﻲ‪ ‬ﺍﻟﺰﻳﺎﺩﺓ‪ ‬ﻓﻲ‪ ‬ﻭﺯﻥ‪ ‬ﺍﻟﺠﺴﻢ‪ ‬ﻓﻲ‪ ‬ﺍﻟﻔﺘﺮﺓ ‪ 56 – 35 ‬ﻳﻮﻡ‪ ‬ﻣﻦ‪ ‬ﺍﻟﻌﻤ‪ ‬ﺮ‪ . ‬ﺑﻴﻨﻤ‪ ‬ﺎ‪ ‬ﺣ‪ ‬ﺪﺙ‪ ‬ﺍﻟﻌﻜ‪ ‬ﺲ‪ ‬ﻓ‪ ‬ﻲ‪ ‬ﺍﻟﻔﺘ‪ ‬ﺮﺓ‪ ‬ﻣ‪ ‬ﻦ ‪64 – 56 ‬‬
‫‪ ‬ﻳﻮﻡ‪ ‬ﻣﻦ‪ ‬ﺍﻟﻌﻤﺮ‪ ‬ﺣﻴﺚ‪ ‬ﺃﺩﺕ‪ ‬ﺇﻟﻰ‪ ‬ﺗﺤﺴﻦ‪ ‬ﻣﻌﻨﻮﻱ‪ ‬ﻓﻲ‪ ‬ﺍﻟﺰﻳﺎﺩﺓ‪ ‬ﻓﻲ‪ ‬ﻭﺯﻥ‪ ‬ﺍﻟﺠﺴﻢ‪ ‬ﻭﺫﻟﻚ‪ ‬ﻋﻨﺪ‪ ‬ﻣﻘﺎﺭﻧﺘﻬﺎ‪ ‬ﺑﻤﺠﻤﻮﻋ‪ ‬ﺔ‪ ‬ﺍﻟﻜﻨﺘ‪ ‬ﺮﻭﻝ‪ ‬ﺍﻹﻳﺠ‪ ‬ﺎﺑﻲ‪ . ‬ﺑﻴﻨﻤ‪ ‬ﺎ‬
‫‪ ‬ﻟﻢ‪ ‬ﻳﻜﻦ‪ ‬ﻫﻨﺎﻙ‪ ‬ﻓﺮﻭﻕ‪ ‬ﻣﻌﻨﻮﻳﺔ‪ ‬ﻓﻲ‪ ‬ﺍﻟﺰﻳﺎﺩﺓ‪ ‬ﻓﻲ‪ ‬ﻭﺯﻥ‪ ‬ﺍﻟﺠﺴﻢ‪ ‬ﺧ‪ ‬ﻼﻝ‪ ‬ﺍﻟﻔﺘﺮﺓ‪ ‬ﻣﻦ ‪ 35 – 1 ‬ﻳﻮﻡ‪ ‬ﻣﻦ‪ ‬ﺍﻟﻌﻤﺮ‪ ‬ﺃﻭ‪ ‬ﺧﻼﻝ‪ ‬ﺍﻟﻔﺘﺮﺓ‪ ‬ﺍﻟﻜﻠﻴﺔ ‪64 – 1 ) ‬‬
‫‪ ‬ﻳﻮﻡ‪ ‬ﻣﻦ‪ ‬ﺍﻟﻌﻤﺮ‪.( ‬‬
‫‪ ­ 4 ‬ﺑﻐ‪ ‬ﺾ‪ ‬ﺍﻟﻨﻈ‪ ‬ﺮ‪ ‬ﻋ‪ ‬ﻦ‪ ‬ﻣﺤﺘ‪ ‬ﻮﻱ‪ ‬ﺍﻟﻌﻠ‪ ‬ﻒ‪ ‬ﻣ‪ ‬ﻦ‪ ‬ﺍﻟﺒ‪ ‬ﺮﻭﺗﻴﻦ‪ ‬ﺍﻟﺨ‪ ‬ﺎﻡ‪ ‬ﻭ‪ ‬ﺍﻟﻄﺎﻗ‪ ‬ﺔ‪ ‬ﺍﻟﻤﻤﺜﻠ‪ ‬ﺔ‪ ‬ﺃﺩﻯ‪ ‬ﺇﺿ‪ ‬ﺎﻓﺔ‪ ‬ﺍﻟﻔﻴﺘ‪ ‬ﺰ‪ ‬ﺍﻟﻔﻄ‪ ‬ﺮﻱ‪ ‬ﺃﻭ‪ ‬ﺍﻟﺒﻜﺘﻴ‪ ‬ﺮﻱ‪ ‬ﺇﻟ‪ ‬ﻰ‬
‫‪ ‬ﺍﻧﺨﻔﺎﺽ‪ ‬ﻣﻌﻨﻮﻱ‪ ‬ﻓﻲ‪ ‬ﺍﻟﺰﻳﺎﺩﺓ‪ ‬ﻓﻲ‪ ‬ﻭﺯﻥ‪ ‬ﺍﻟﺠﺴﻢ‪ ‬ﻓﻲ‪ ‬ﺍﻟﻔﺘﺮﺓ ‪ 56 – 35 ‬ﻳﻮﻡ‪ ‬ﻣﻦ‪ ‬ﺍﻟﻌﻤﺮ‪ . ‬ﺑﻴﻨﻤﺎ‪ ‬ﺣﺪ‪ ‬ﺙ‪ ‬ﺍﻟﻌﻜﺲ ‪ ‬ﺣﻴﺚ‪ ‬ﺗﺤﺴﻨﺖ‪ ‬ﻣﻌﻨﻮﻳﺎ‪ ‬ﺍﻟﺰﻳﺎﺩﺓ‬
‫‪ ‬ﻓﻲ‪ ‬ﻭﺯﻥ‪ ‬ﺍﻟﺠﺴﻢ‪ ‬ﺧﻼﻝ‪ ‬ﺍﻟﻔﺘﺮﺓ ‪ 64 – 56 ‬ﻳﻮﻡ‪ ‬ﻣﻦ‪ ‬ﺍﻟﻌﻤﺮ‪ ‬ﻧﺘﻴﺠﺔ‪ ‬ﺇﺿﺎﻓﺔ‪ ‬ﺍﻹﻧﺰﻳﻢ‪ ‬ﺍﻟﻔﻄﺮﻱ‪ ‬ﻭ‪ ‬ﺫﻟ‪ ‬ﻚ‪ ‬ﺑﺎﻟﻤﻘﺎﺭﻧ‪ ‬ﺔ‪ ‬ﺑﺈﺿ‪ ‬ﺎﻓﺔ‪ ‬ﺍﻹﻧ‪ ‬ﺰﻳﻢ‪ ‬ﺍﻟﺒﻜﺘﻴ‪ ‬ﺮﻱ‬
‫‪ ‬ﺃﻭ‪ ‬ﺍﻟﻜﻨﺘﺮﻭﻝ‪ ٬‬ﺑﻴﻨﻤﺎ‪ ‬ﻻ‪ ‬ﺗﻮﺟﺪ‪ ‬ﺍﺧﺘﻼﻓﺎ‪ ‬ﺕ ‪ ‬ﻣﻌﻨﻮﻳﺔ‪ ‬ﺑﻴﻦ‪ ‬ﻣﺠﻤﻮﻋﺎﺕ‪ ‬ﺇﺿ‪ ‬ﺎﻓﺔ‪ ‬ﺍﻟﻔﻴﺘ‪ ‬ﺰ‪ ‬ﺃﻭ‪ ‬ﻋ‪ ‬ﺪﻡ‪ ‬ﺇﺿ‪ ‬ﺎﻓﺘﻪ‪ ‬ﺧ‪ ‬ﻼﻝ‪ ‬ﺍﻟﻔﺘ‪ ‬ﺮﺓ‪ ‬ﻣ‪ ‬ﻦ ‪ 35 – 1 ‬ﻳ‪ ‬ﻮﻡ‪ ‬ﻣ‪ ‬ﻦ‬
‫‪ ‬ﺍﻟﻌﻤﺮ‪ ‬ﺃﻭ‪ ‬ﺍﻟﻔﺘﺮﺓ‪ ‬ﺍﻟﻜﻠﻴﺔ ‪ 64 – 1 ‬ﻳﻮﻡ‪ ‬ﻣﻦ‪ ‬ﺍﻟﻌﻤﺮ‪. ‬‬
‫‪ ­ 5 ‬ﺃﺩﺕ‪ ‬ﺍﻟﻤﻌﺎﻣﻼﺕ‪ ‬ﺍﻟﺘﺠﺮﻳﺒﻴﺔ‪ ‬ﺍﻟﻤﺨﺘﻠﻔﺔ‪ ‬ﺇﻟﻰ‪ ‬ﺍﻧﺨﻔﺎﺽ‪ ‬ﻣﻌﻨﻮﻱ‪ ‬ﻓﻲ‪ ‬ﺍﻟﻐﺬﺍء‪ ‬ﺍﻟﻤﺄﻛﻮﻝ‪ ‬ﺧﻼﻝ‪ ‬ﺍﻟﻔﺘ‪ ‬ﺮﺍﺕ‪ ‬ﻣ‪ ‬ﻦ ‪ 35 – 1 ‬ﻳ‪ ‬ﻮﻡ‪56 – 36 ٬‬‬
‫‪ ‬ﻳﻮﻡ‪ ‬ﻣﻦ‪ ‬ﺍﻟﻌﻤﺮ‪ ‬ﻭﻛﺬﻟﻚ‪ ‬ﺧﻼﻝ‪ ‬ﺍﻟﻔﺘﺮﺓ‪ ‬ﺍﻟﻜﻠﻴﺔ ‪ 64 – 1 ‬ﻳﻮﻡ‪ ‬ﻣﻦ‪ ‬ﺍﻟﻌﻤﺮ‪ ‬ﻭﺫﻟﻚ‪ ‬ﻋﻨﺪ‪ ‬ﻣﻘﺎﺭﻧﺘﻬﺎ‪ ‬ﺑﻤﺠﻤﻮﻋﺔ‪ ‬ﺍﻟﻜﻨﺘﺮﻭﻝ‪ ‬ﺍﻹﻳﺠ‪ ‬ﺎﺑﻲ‪ ‬ﻭﻳﺴ‪ ‬ﺘﺜ‪ ‬ﻨﻰ‪ ‬ﻣ‪ ‬ﻦ‬
‫‪ ‬ﺫﻟﻚ‪ ‬ﻣﺠﻤﻮﻋﺔ‪ ‬ﺧﻔﺾ‪ ‬ﺍﻟﻌﻠﻒ‪ ‬ﻣﻦ‪ ‬ﺍﻟﺒﺮﻭﺗﻴﻦ‪ ‬ﺍﻟﺨ‪ ‬ﺎﻡ‪ ‬ﺣﻴ‪ ‬ﺚ‪ ‬ﻻ‪ ‬ﺗﻮﺟ‪ ‬ﺪ‪ ‬ﺑﻴﻨﻬ‪ ‬ﺎ‪ ‬ﻭ‪ ‬ﺑ‪ ‬ﻴﻦ‪ ‬ﻣﺠﻤﻮﻋ‪ ‬ﺔ‪ ‬ﺍﻟﻜﻨﺘ‪ ‬ﺮﻭﻝ‪ ‬ﺍﻹﻳﺠ‪ ‬ﺎﺑﻲ‪ ‬ﺍﺧﺘﻼﻓ‪ ‬ﺎﺕ‪ ‬ﻣﻌﻨﻮﻳ‪ ‬ﺔ‪ ‬ﻓ‪ ‬ﻲ‬
‫‪ ‬ﺍﻟﻔﺘﺮﺓ‪ ‬ﻣﻦ ‪ 56 ­ 35 ‬ﻳﻮﻡ‪ ‬ﻣﻦ‪ ‬ﺍﻟﻌﻤﺮ‪ ‬ﻣﻊ‪ ‬ﻣﻼﺣﻈﺔ‪ ‬ﺃﻥ‪ ‬ﺇﺿﺎﻓﺔ‪ ‬ﺍﻟﻔﻴﺘﺰ‪ ‬ﺍﻟﺒﻜﺘﻴﺮﻱ‪ ‬ﺇﻟﻲ ‪ ‬ﻣﺠﻤﻮﻋﺔ‪ ‬ﺧﻔﺾ‪ ‬ﻣﺤﺘﻮﻯ‪ ‬ﺍﻟﻌﻠﻒ‪ ‬ﻣﻦ‪ ‬ﺍﻟﺒ‪ ‬ﺮﻭﺗﻴﻦ‪ ‬ﺍﻟﺨ‪ ‬ﺎﻡ‬
‫‪ ‬ﺃﻭ‪ ‬ﺧﻔ‪ ‬ﺾ‪ ‬ﻣﺤﺘ‪ ‬ﻮﻱ‪ ‬ﺍﻟﻌﻠ‪ ‬ﻒ‪ ‬ﻣ‪ ‬ﻦ‪ ‬ﺍﻟﺒ‪ ‬ﺮﻭﺗﻴﻦ‪ ‬ﺍﻟﺨ‪ ‬ﺎﻡ‪ ‬ﻭ‪ ‬ﺍﻟﻄﺎﻗ‪ ‬ﺔ‪ ‬ﺍﻟﻤﻤﺜﻠ‪ ‬ﺔ‪ ‬ﻗﻠﻠ‪ ‬ﺖ‪ ‬ﻣﻌﻨﻮﻳ‪ ‬ﺎ‪ ‬ﻣ‪ ‬ﻦ‪ ‬ﻛﻤﻴ‪ ‬ﺔ‪ ‬ﺍﻟﻐ‪ ‬ﺬﺍء‪ ‬ﺍﻟﻤ‪ ‬ﺄﻛﻮﻝ‪ ‬ﻋ‪ ‬ﻦ‪ ‬ﺑ‪ ‬ﺎﻗﻲ‪ ‬ﺍﻟﻤﺠﻤﻮﻋ‪ ‬ﺎﺕ‬
‫‪ ‬ﺍﻷﺧﺮﻯ‪ ‬ﺧﻼﻝ‪ ‬ﺍﻟﻔﺘﺮﺓ ‪ 56 – 35 ‬ﻳﻮﻡ‪ ‬ﻣﻦ‪ ‬ﺍﻟﻌﻤﺮ‪. ‬‬
‫‪ ­ 6 ‬ﻟﻮﺣﻈﺖ‪ ‬ﺍﺧﺘﻼﻓﺎﺕ‪ ‬ﻣﻌﻨﻮﻳﺔ‪ ‬ﻓﻲ‪ ‬ﻛﻤﻴﺔ‪ ‬ﺍﻟﻐﺬﺍء‪ ‬ﺍﻟﻤﺄﻛﻮﻝ‪ ‬ﻧﺘﻴﺠﺔ‪ ‬ﺇﺿﺎﻓﺔ‪ ‬ﺍﻹﻧﺰﻳﻢ‪ ‬ﺍﻟﺒﻜﺘﻴ‪ ‬ﺮﻱ‪ ‬ﺇﻟ‪ ‬ﻲ‪ ‬ﺍﻟﻌﻼﺋ‪ ‬ﻖ‪ ‬ﺍﻟﻤﻨﺨﻔﻀ‪ ‬ﺔ‪ ‬ﻓ‪ ‬ﻲ‪ ‬ﺍﻟﺒ‪ ‬ﺮﻭﺗﻴﻦ‬
‫‪ ‬ﺍﻟﺨﺎﻡ‪ ‬ﺃﻭ‪ ‬ﺍﻟﺒﺮﻭﺗﻴﻦ‪ ‬ﺍﻟﺨﺎﻡ‪ ‬ﻭ‪ ‬ﺍﻟﻄﺎﻗﺔ‪ ‬ﺍﻟ‪ ‬ﻤﻤﺜﻠﺔ‪ ‬ﻭ‪ ‬ﺳﺠﻠﺖ‪ ‬ﻫﺎﺗﻴﻦ‪ ‬ﺍﻟﻤﺠﻤ‪ ‬ﻮﻋﺘﻴﻦ‪ ‬ﺃﻗ‪ ‬ﻞ‪ ‬ﺍﺳ‪ ‬ﺘﻬﻼﻙ‪ ‬ﻏ‪ ‬ﺬﺍﺋﻲ‪ ‬ﺧ‪ ‬ﻼﻝ‪ ‬ﺍﻟﻔﺘ‪ ‬ﺮﺓ‪ ‬ﺍﻟﻜﻠﻴ‪ ‬ﺔ‪ ‬ﻟﻠﺘﺠﺮﺑ‪ ‬ﺔ‪ ‬ﻭ‪ ‬ﻛ‪ ‬ﺎﻥ‬
‫‪ ‬ﻫﻨﺎﻙ‪ ‬ﻧﻘﺺ‪ ‬ﺃﻳﻀﺎ‪ ‬ﻓﻲ‪ ‬ﺍﺳﺘﻬﻼﻙ‪ ‬ﺍﻟﻌﻠﻒ‪ ‬ﻓﻲ‪ ‬ﺍﻟﻤﺠﺎﻣﻴﻊ‪ ‬ﺍﻻﺧﺮﻱ‪ ‬ﻣﻘﺎﺭﻧﺔ‪ ‬ﺑﻤﺠﻤﻮﻋﺔ‪ ‬ﺍﻟﻜﻨﺘﺮﻭﻝ‪ ‬ﺍﻻﻳﺠﺎﺑﻲ‪ ‬ﻭ‪ ‬ﻟﻜﻦ‪ ‬ﻛﺎﻥ‪ ‬ﺃﻗﻞ ‪ ‬ﺿﺮﺍﻭﺓ‪. ‬‬
‫‪ ­ 7 ‬ﺑﻐﺾ‪ ‬ﺍﻟﻨﻈﺮ‪ ‬ﻋﻦ‪ ‬ﻧ‪ ‬ﻮﻉ‪ ‬ﺍﻹﻧ‪ ‬ﺰﻳﻢ‪ ٬ ‬ﺃﺩﻯ‪ ‬ﺧﻔ‪ ‬ﺾ‪ ‬ﻣﺤﺘ‪ ‬ﻮﻯ‪ ‬ﺍﻟﻌﻠ‪ ‬ﻒ‪ ‬ﻣ‪ ‬ﻦ‪ ‬ﺍﻟﺒ‪ ‬ﺮﻭﺗﻴﻦ‪ ‬ﺍﻟﺨ‪ ‬ﺎﻡ‪ ‬ﺃﻭ‪ ‬ﺍﻟﺒ‪ ‬ﺮﻭﺗﻴﻦ‪ ‬ﺍﻟﺨ‪ ‬ﺎﻡ‪ ‬ﻭﺍﻟﻄﺎﻗ‪ ‬ﺔ‪ ‬ﺍﻟﻤﻤﺜﻠ‪ ‬ﺔ‪ ‬ﺇﻟ‪ ‬ﻰ‬
‫‪ ‬ﺍﻧﺨﻔﺎﺽ‪ ‬ﻣﻌﻨﻮﻱ‪ ‬ﻓﻲ‪ ‬ﺍﻟﻐﺬﺍء‪ ‬ﺍﻟﻤﺄﻛﻮﻝ‪ ‬ﻓﻲ ‪ ‬ﻏﺎﻟﺒﻴﺔ‪ ‬ﺍﻟﻔﺘﺮﺍﺕ‪ ‬ﺍﻟﺘﺠﺮﺑﻴﺒﺔ‪ ‬ﻭﺑﻐﺾ‪ ‬ﺍﻟﻨﻈﺮ‪ ‬ﻋﻦ‪ ‬ﻣﺤﺘﻮﻱ‪ ‬ﺍﻟﻌﻠﻒ‪ ‬ﻣﻦ‪ ‬ﺍﻟﺒ‪ ‬ﺮﻭﺗﻴﻦ‪ ‬ﺍﻟﺨ‪ ‬ﺎﻡ‪ ‬ﻭ‪ ‬ﺍﻟﻄﺎﻗ‪ ‬ﺔ‬
‫‪ ‬ﺍﻟﻤﻤﺜﻠﺔ‪ ‬ﺃﺩﻯ‪ ‬ﺇﺿﺎﻓﺔ‪ ‬ﺍﻟﻔﻴﺘﺰ‪ ‬ﺍﻟﻔﻄﺮﻱ‪ ‬ﺃﻭ‪ ‬ﺍﻟﺒﻜﺘﻴﺮﻱ‪ ‬ﺇﻟﻰ‪ ‬ﺍﻧﺨﻔﺎﺽ‪ ‬ﻣﻌﻨﻮﻱ‪ ‬ﻓﻲ‪ ‬ﻛﻤﻴﺔ‪ ‬ﺍﻟﻐﺬﺍء‪ ‬ﺍﻟﻤﺄﻛﻮﻝ‪ ‬ﻣﻘﺎﺭﻧﺔ‪ ‬ﺑﻌﺪﻡ‪ ‬ﺇﺿﺎﻓﺔ‪ ‬ﺍﻷﻧ‪ ‬ﺰﻳﻢ‪ ‬ﻓ‪ ‬ﻲ ﻛ‪ ‬ﻞ‬
‫‪ ‬ﺍﻟﻔﺘﺮﺍﺕ‪ ‬ﺍﻟﺘﺠﺮﺑﻴﺒﺔ‪ ‬ﻣﻊ‪ ‬ﻣﻼﺣﻈﺔ‪ ‬ﺃﻥ‪ ‬ﺇﺿﺎﻓﺔ‪ ‬ﺍﻟﻔﻴﺘﺰ‪ ‬ﺍﻟﺒﻜﺘﻴﺮﻱ‪ ‬ﺃﺩﻯ‪ ‬ﺇﻟﻰ‪ ‬ﺍﻧﺨﻔﺎﺽ‪ ‬ﻣﻌﻨﻮﻱ‪ ‬ﻓﻲ‪ ‬ﻛﻤﻴﺔ‪ ‬ﺍﻟﻐﺬﺍء‪ ‬ﺍﻟﻤﺄﻛﻮﻝ‪ ‬ﻣﻘﺎﺭﻧﺔ‪ ‬ﺑﺈﻧﺰﻳﻢ‪ ‬ﺍﻟﻔﻴﺘ‪ ‬ﺰ‬
‫‪ ‬ﺍﻟﻔﻄﺮﻱ‪ ‬ﻭﺫﻟﻚ‪ ‬ﺧﻼﻝ‪ ‬ﺍﻟﻔﺘﺮﺓ‪ ‬ﻣﻦ ‪ 35 ­ 1 ‬ﻳﻮﻡ‪ ‬ﻭﺍﻟﻔﺘﺮﺓ‪ ‬ﻣﻦ‪ 64 ­ 56 ‬ﻭﺍﻟﻔﺘﺮﺓ‪ ‬ﺍﻟﻜﻠﻴﺔ‪ ‬ﻣﻦ ‪ 64 ­ 1 ‬ﻳﻮﻡ‪.‬‬
‫‪109 ‬‬
‫‪ ­ 8 ‬ﺧﻼﻝ‪ ‬ﺍﻟﻔﺘﺮﺓ‪ ‬ﻣﻦ ‪ 56 ­ 36 ‬ﻳﻮﻡ‪ ‬ﻣﻦ‪ ‬ﺍﻟﻌﻤﺮ‪ ‬ﺃﺩﺕ‪ ‬ﺍﻟﻤﻌﺎﻣﻼﺕ‪ ‬ﺍﻟﺘﺠ‪ ‬ﺮﻳﺒﻴﺔ‪ ‬ﺍﻟﻤﺨﺘﻠﻔﺔ‪ ‬ﺇﻟ‪ ‬ﻰ‪ ‬ﺳ‪ ‬ﻮء‪ ‬ﻛﻔ‪ ‬ﺎءﺓ‪ ‬ﺍﻟﺘﺤﻮﻳ‪ ‬ﻞ‪ ‬ﺍﻟﻐ‪ ‬ﺬﺍء‪ ‬ﻣﻌﻨﻮﻳ‪ ‬ﺎ‪ ‬ﻋﻨ‪ ‬ﺪ‬
‫‪ ‬ﻣﻘﺎﺭﻧﺘﻬﺎ‪ ‬ﺑﻤﺠﻤﻮﻋﺔ‪ ‬ﺍﻟﻜﻨﺘﺮﻭﻝ‪ ‬ﺍﻹﻳﺠﺎﺑـﻲ‪ ‬ﺣﻴ‪ ‬ﺚ‪ ‬ﻛ‪ ‬ﺎﻥ‪ ‬ﺃﺳ‪ ‬ﻮ‪ ‬ﺃ‪ ‬ﻣﻌ‪ ‬ﺪﻝ‪ ‬ﻟﻠﺘﺤﻮﻳ‪ ‬ﻞ‪ ‬ﺍﻟﻐ‪ ‬ﺬﺍﺋﻲ‪ ‬ﻟﻤﺠﻤﻮﻋ‪ ‬ﺔ‪ ‬ﺧﻔ‪ ‬ﺾ‪ ‬ﻣﺤﺘ‪ ‬ﻮﻯ‪ ‬ﺍﻟﻌﻠ‪ ‬ﻒ‪ ‬ﻣ‪ ‬ﻦ‪ ‬ﺍﻟﺒ‪ ‬ﺮﻭﺗﻴﻦ‬
‫‪ ‬ﺍﻟﺨﺎﻡ‪ ‬ﻣـﻊ‪ ‬ﺇﺿﺎﻓﺔ‪ ‬ﺍﻟﻔﻴﺘﺰ‪ ‬ﺍﻟﻔﻄﺮﻱ‪ ٬‬ﺑﻴﻨﻤﺎ‪ ‬ﺧﻼﻝ‪ ‬ﺍﻟﻔﺘﺮﺓ‪ ‬ﻣﻦ ‪ 64 ­ 56 ‬ﻳﻮﻡ‪ ‬ﺗﺤﺴﻦ‪ ‬ﻣﻌﻨﻮﻳﺎ‪ ‬ﻣﻌﺪﻝ‪ ‬ﺗﺤﻮﻳﻞ‪ ‬ﺍﻟﻐﺬﺍء‪ ‬ﻓ‪ ‬ﻲ‪ ‬ﺍﻟﻤﻌ‪ ‬ﺎﻣﻼﺕ‪ ‬ﺍﻟﺘﺠﺮﺑﻴﺒ‪ ‬ﺔ‬
‫‪ ‬ﺍﻟﻤﺨﺘﻠﻔﺔ‪ ‬ﻣﻘﺎﺭﻧﺔ‪ ‬ﺑﻤﺠﻤﻮﻋﺔ‪ ‬ﺍﻟﻜﻨﺘﺮﻭﻝ‪ ‬ﺍﻻﻳﺠﺎﺑﻲ‪ ‬ﺣﻴﺚ‪ ‬ﺳﺠﻠﺖ‪ ‬ﻣﺠﻤﻮﻋﺔ ‪ ‬ﺧﻔﺾ‪ ‬ﻣﺴﺘﻮﻱ‪ ‬ﺍﻟﺒ‪ ‬ﺮﻭﺗﻴﻦ‪ ‬ﺍﻟﺨ‪ ‬ﺎﻡ‪ ‬ﻓ‪ ‬ﻲ‪ ‬ﻭﺟ‪ ‬ﻮﺩ‪ ‬ﺍﻹﻧ‪ ‬ﺰﻳﻢ‪ ‬ﺍﻟﻔﻄ‪ ‬ﺮﻱ‬
‫‪ ‬ﺃﻓﻀﻞ‪ ‬ﻛﻔﺎءﺓ‪ ‬ﺗﺤﻮﻳﻠﻴﺔ‪ ‬ﻭ‪ ‬ﻟﻢ‪ ‬ﻳﻜﻦ‪ ‬ﻫﻨﺎﻙ‪ ‬ﻓﺮﻭﻕ‪ ‬ﻣﻌﻨﻮﻳﺔ‪ ‬ﺑﻴﻦ‪ ‬ﻛﻞ‪ ‬ﻣﻦ‪ ‬ﻣﺠﻤﻮﻋﺔ‪ ‬ﺧﻔﺾ‪ ‬ﻧﺴﺒﺔ‪ ‬ﺍﻟﺒﺮﻭﺗﻴﻦ‪ ‬ﺍﻟﺨﺎﻡ‪ ‬ﻓﻲ‪ ‬ﺍﻟﻌﻠﻒ‪ ‬ﻣﻊ‪ ‬ﺇﺿﺎﻓﺔ‪ ‬ﺍﻟﻔﻴﺘ‪ ‬ﺰ‬
‫‪ ‬ﺍﻟﻔﻄﺮﻱ‪ ‬ﻭﻣﺠﻤﻮﻋﺔ‪ ‬ﺧﻔﺾ‪ ‬ﻣﺤﺘﻮﻱ‪ ‬ﺍﻟﻌﻠﻒ‪ ‬ﻣﻦ‪ ‬ﺍﻟﺒﺮﻭﺗﻴﻦ‪ ‬ﺍﻟﺨﺎﻡ‪ ‬ﻭﺍﻟﻄﺎﻗﺔ‪ ‬ﺍﻟﻤﻤﺜﻠﺔ‪ ‬ﻣﻊ‪ ‬ﺇﺿﺎﻓﺔ‪ ‬ﺍﻟﻔﻴﺘﺰ‪ ‬ﺍﻟﺒﻜﺘﻴ‪ ‬ﺮﻱ‪ ‬ﻭﻣﺠﻤﻮﻋ‪ ‬ﺔ ‪ ‬ﺧﻔ‪ ‬ﺾ‪ ‬ﻧﺴ‪ ‬ﺒﺔ‬
‫‪ ‬ﺍﻟﺒﺮﻭﺗﻴﻦ‪ ‬ﺍﻟﺨﺎﻡ‪ ‬ﻓﻲ‪ ‬ﻣﺤﺘﻮﻯ‪ ‬ﺍﻟﻌﻠﻒ‪ ‬ﻭ‪ ‬ﺧﻔ‪ ‬ﺾ‪ ‬ﻣﺤﺘ‪ ‬ﻮﻯ‪ ‬ﺍﻟﻌﻠ‪ ‬ﻒ‪ ‬ﻣ‪ ‬ﻦ‪ ‬ﺍﻟﺒ‪ ‬ﺮﻭﺗﻴﻦ‪ ‬ﺍﻟﺨ‪ ‬ﺎﻡ‪ ‬ﻭﺍﻟﻄﺎﻗ‪ ‬ﺔ‪ ‬ﺍﻟﻤﻤﺜﻠ‪ ‬ﺔ‪ ‬ﺑ‪ ‬ﺪﻭﻥ‪ ‬ﺇﺿ‪ ‬ﺎﻓﺔ‪ ‬ﺍﻟﻔﻴﺘ‪ ‬ﺰ‪ ‬ﻭﻟﻜ‪ ‬ﻦ‪ ‬ﻫ‪ ‬ﺬﺓ‬
‫‪ ‬ﺍﻟﻤﺠﻤﻮﻋﺎﺕ‪ ‬ﻛﺎﻧﺖ‪ ‬ﺫﺍﺕ‪ ‬ﻣﻌﺪﻝ‪ ‬ﺗﺤﻮﻳﻞ‪ ‬ﻏﺬﺍﺋﻲ‪ ‬ﺃﻓﻀﻞ‪ ‬ﻣﻦ‪ ‬ﺍﻟﻤﻌﺎﻣﻼﺕ‪ ‬ﺍﻟﺘﺠﺮ‪ ‬ﺑﻴﺒﺔ‪ ‬ﺍﻻﺧﺮﻱ‪. ‬‬
‫‪ ­ 9 ‬ﺧﻼﻝ‪ ‬ﺍﻟﻔﺘﺮﺓ‪ ‬ﺍﻟﻜﻠﻴﺔ‪ ‬ﻟﻠﺘﺠﺮﺑﺔ‪ ‬ﺗﺤﺴﻦ‪ ‬ﻣﻌﺪﻝ‪ ‬ﺗﺤﻮﻳ‪ ‬ﻞ‪ ‬ﺍﻟﺒ‪ ‬ﺮﻭﺗﻴﻦ‪ ‬ﺍﻟﺨ‪ ‬ﺎﻡ‪ ‬ﺃﻭ‪ ‬ﺍﻟﻄﺎﻗ‪ ‬ﺔ‪ ‬ﺍﻟﻤﻤﺜﻠ‪ ‬ﺔ‪ ‬ﻧﺘﻴﺠ‪ ‬ﺔ‪ ‬ﺍﺳ‪ ‬ﺘﺨﺪﺍﻡ‪ ‬ﺍﻟﻌﻠ‪ ‬ﻒ‪ ‬ﺍﻟﻤ‪ ‬ﻨﺨﻔﺾ‪ ‬ﻓ‪ ‬ﻲ‬
‫‪ ‬ﺍﻟﺒﺮﻭﺗﻴﻦ‪ ‬ﺍﻟﺨﺎﻡ‪ ‬ﺃﻭ‪ ‬ﺍﻟﺒﺮﻭﺗﻴﻦ‪ ‬ﺍﻟﺨﺎﻡ‪ ‬ﻭ‪ ‬ﺍﻟﻄﺎﻗﺔ‪ ‬ﺍﻟﻤﻤﺜﻠﺔ‪ ‬ﻣﻘﺎﺭﻧﺔ‪ ‬ﺑﻤﺠﻤﻮﻋﺔ‪ ‬ﺍﻟﻜﻨﺘ‪ ‬ﺮﻭﻝ‪ ‬ﻭ‪ ‬ﻟ‪ ‬ﻢ‪ ‬ﻳﻜ‪ ‬ﻦ‪ ‬ﻟﻨ‪ ‬ﻮﻉ‪ ‬ﺍﻟﻔﻴﺘﻴ‪ ‬ﺰ‪ ‬ﺃﻭ‪ ‬ﺍﻟﺘ‪ ‬ﺪﺍﺧﻞ‪ ‬ﺑ‪ ‬ﻴﻦ‪ ‬ﺍﻹﻧ‪ ‬ﺰﻳﻢ‪ ‬ﻭ‬
‫‪ ‬ﺧﻔ‪ ‬ﺾ‪ ‬ﻣﺴ‪ ‬ﺘﻮﻱ‪ ‬ﺍﻟﺒ‪ ‬ﺮﻭ‪ ‬ﺗﻴﻦ‪ ‬ﺍﻟﺨ‪ ‬ﺎﻡ‪ ‬ﺃﻭ‪ ‬ﺍﻟﺒ‪ ‬ﺮﻭﺗﻴﻦ‪ ‬ﺍﻟﺨ‪ ‬ﺎﻡ‪ ‬ﻭﺍﻟﻄﺎﻗ‪ ‬ﺔ‪ ‬ﺍﻟﻤﻤﺜﻠ‪ ‬ﺔ‪ ‬ﺗ‪ ‬ﺄﺛﻴﺮ‪ ‬ﻣﻌﻨ‪ ‬ﻮﻱ‪ ‬ﻋﻠ‪ ‬ﻲ‪ ‬ﻣﻌ‪ ‬ﺪﻝ‪ ‬ﺗﺤﻮﻳ‪ ‬ﻞ‪ ‬ﺍﻟﺒ‪ ‬ﺮﻭﺗﻴﻦ‪ ‬ﺍﻟﺨ‪ ‬ﺎﻡ‪ ‬ﺃﻭ‪ ‬ﺍﻟﻄﺎﻗ‪ ‬ﺔ‬
‫‪ ‬ﺍﻟﻤﻤﺜﻠﺔ‪. ‬‬
‫‪ ­ 10 ‬ﻟﻢ‪ ‬ﺗﻜﻦ‪ ‬ﻫﻨﺎﻙ‪ ‬ﺍﺧﺘﻼﻓﺎﺕ‪ ‬ﻣﻌﻨﻮﻳﺔ‪ ‬ﻧﺘﻴﺠﺔ‪ ‬ﺍﺧﺘﻼﻓ‪ ‬ﺎﺕ‪ ‬ﻣﺴ‪ ‬ﺘﻮﻱ‪ ‬ﺍﻟﺒ‪ ‬ﺮﻭﺗﻴﻦ‪ ‬ﺍﻟﺨ‪ ‬ﺎﻡ‪ ‬ﻭ‪ ‬ﺍﻟﻄﺎﻗ‪ ‬ﺔ‪ ‬ﺍﻟﻤﻤﺜﻠ‪ ‬ﺔ‪ ‬ﻭ‪ / ‬ﺃﻭ‪ ‬ﻧﻮﻋﻴ‪ ‬ﺔ‪ ‬ﺍﻟﻔﻴﺘﻴ‪ ‬ﺰ‪ ‬ﻓ‪ ‬ﻲ ‪ ‬ﻛﻔ‪ ‬ﺎءﺓ‬
‫‪ ‬ﺍﻟﺘﺤﻮﻳﻞ‪ ‬ﺍﻟﻐﺬﺍﺋﻲ‪ ‬ﺧ‪ ‬ﻼﻝ‪ ‬ﺍﻟﻔﺘ‪ ‬ﺮﺓ‪ ‬ﺍﻟﻜﻠﻴ‪ ‬ﺔ‪ ‬ﻟﻠﺘﺠﺮﺑ‪ ‬ﺔ‪ ‬ﻣ‪ ‬ﻦ‪ 35 ­ 1 ‬ﻭ ‪ 64 ­ 1 ‬ﻳ‪ ‬ﻮﻡ‪ ‬ﻣ‪ ‬ﻦ‪ ‬ﺍﻟﻌﻤ‪ ‬ﺮ‪ ‬ﻭ‪ ‬ﻟﻜ‪ ‬ﻦ‪ ‬ﺳ‪ ‬ﺠﻠﺖ‪ ‬ﻣﺠﻤﻮﻋ‪ ‬ﺔ‪ ‬ﺍﻟﻜﻨﺘ‪ ‬ﺮﻭﻝ‪ ‬ﺍﻻﻳﺠ‪ ‬ﺎﺑﻲ‬
‫‪ ‬ﺃﻓﻀﻞ‪ ‬ﻣﻌﺪﻝ‪ ‬ﺗﺤﻮﻳﻞ‪ ‬ﻏﺬﺍﺋﻴ‪ ‬ﺔ ‪ ‬ﺧﻼﻝ‪ ‬ﺍﻟﻔﺘﺮﺓ‪ ‬ﺍﻟﻜﻠﻴﺔ‪ ‬ﻟﻠﺘﺠﺮﺑﺔ‪. ‬‬
‫‪ ­ 11 ‬ﻟﻢ‪ ‬ﺗﺘﺄﺛﺮ‪ ‬ﻣﻌﺪﻻﺕ‪ ‬ﺍﻟﻨﻔﻮﻕ‪ ‬ﺧﻼﻝ‪ ‬ﺍﻟﻔﺘﺮﺍﺕ‪ ‬ﺍﻟﺘﺠﺮﺑﻴﺒﺔ‪ ‬ﻧﺘﻴﺠﺔ‪ ‬ﺍﺧﺘﻼﻓ‪ ‬ﺎﺕ‪ ‬ﻣﺴ‪ ‬ﺘﻮﻱ‪ ‬ﺍﻟﺒ‪ ‬ﺮﻭﺗﻴﻦ‪ ‬ﺍﻟﺨ‪ ‬ﺎﻡ‪ ‬ﻭ‪ ‬ﺍﻟﻄﺎﻗ‪ ‬ﺔ‪ ‬ﺍﻟﻤﻤﺜﻠ‪ ‬ﺔ‪ ‬ﻭ‪ / ‬ﺃﻭ‪ ‬ﻧﻮﻋﻴ‪ ‬ﺔ‬
‫‪ ‬ﺍﻟﻔﻴﺘﻴﺰ‪ ‬ﻭ‪ ‬ﻛﺎﻧﺖ‪ ‬ﻣﻌﺪﻻﺕ‪ ‬ﺍﻟﻨﻤﻮ‪ ‬ﻓﻲ‪ ‬ﺣﺪﻭﺩ‪ ‬ﺍﻟﻤﻌﺪﻻﺕ‪ ‬ﺍﻟﻄﺒﻴﻌﻴﺔ‪ ‬ﻟﺪﺟﺎﺝ‪ ‬ﺍﻟﻠﺤﻢ‪. ‬‬
‫‪ ­ 12 ‬ﻟﻢ‪ ‬ﺗﻜﻦ‪ ‬ﻫﻨﺎﻙ‪ ‬ﺍﺧﺘﻼﻓﺎﺕ‪ ‬ﻣﻌﻨﻮﻳﺔ‪ ‬ﻓﻲ‪ ‬ﻣﻌﺎﻣﻞ‪ ‬ﺍﻟﻬﻀﻢ‪ ‬ﺍﻟﻈ‪ ‬ﺎﻫﺮﻱ‪ ‬ﻟﻜ‪ ‬ﻼً‪ ‬ﻣ‪ ‬ﻦ‪ ‬ﺍﻟﺒ‪ ‬ﺮﻭﺗﻴﻦ‪ ‬ﺍﻟﺨ‪ ‬ﺎﻡ‪ ‬ﻭﺍﻷﻟﻴ‪ ‬ﺎﻑ‪ ‬ﻭﺍﻟ‪ ‬ﺪﻫﻦ‪ ‬ﻭ‪ ‬ﺍﻟﻤ‪ ‬ﺎﺩﺓ‪ ‬ﺍﻟﺠﺎﻓ‪ ‬ﺔ‬
‫‪ ‬ﻭﺫﻟ‪ ‬ﻚ‪ ‬ﺑ‪ ‬ﻴﻦ‪ ‬ﺟﻤﻴ‪ ‬ﻊ‪ ‬ﺍﻟﻤﻌ‪ ‬ﺎﻣﻼﺕ‪ ‬ﺍﻟﺘﺠﺮﻳﺒﻴ‪ ‬ﺔ‪ . ‬ﻣ‪ ‬ﻊ‪ ‬ﻣﻼﺣﻈ‪ ‬ﺔ‪ ‬ﺃﻥ‪ ‬ﺇﺿ‪ ‬ﺎﻓﺔ‪ ‬ﺇﻧ‪ ‬ﺰﻳﻢ‪ ‬ﺍﻟﻔﻴﺘ‪ ‬ﺰ‪ ‬ﺣﺴ‪ ‬ﻦ‪ ‬ﻣﻌﻨﻮﻳ‪ ‬ﺎ‪ ‬ﻣ‪ ‬ﻦ‪ ‬ﻣﻌﺎﻣ‪ ‬ﻞ‪ ‬ﻫﻀ‪ ‬ﻢ‪ ‬ﺍﻟﻤ‪ ‬ﺎﺩﺓ‪ ‬ﺍﻟﺠﺎﻓ‪ ‬ﺔ‪ ‬ﻭ‬
‫‪ ‬ﺍ‪ ‬ﻷﻟﻴﺎﻑ‪ ٬ ‬ﻭ‪ ‬ﺍﻟﺒﺮﻭﺗﻴﻦ‪ ‬ﺍﻟﺨﺎﻡ‪ ‬ﻭﺫﻟﻚ‪ ‬ﻋﻨﺪ‪ ‬ﻣﻘﺎﺭﻧﺘﻪ‪ ‬ﺑﻤﺠﻤﻮﻋﺎﺕ‪ ‬ﻋﺪﻡ‪ ‬ﺇﺿﺎﻓﺔ‪ ‬ﺍﻷﻧﺰﻳﻢ‪ ‬ﻭ‪ ‬ﻟﻜﻦ‪ ‬ﺑﺪﻭﻥ‪ ‬ﻓﺮﻭﻕ‪ ‬ﻣﻌﻨﻮﻳﺔ‪ ‬ﺑﻴﻦ‪ ‬ﻧﻮﻋﻲ‪ ‬ﺍﻟﻔﻴﺘﻴﺰ‪. ‬‬
‫‪ ­ 13 ‬ﻟﻢ‪ ‬ﺗﻜﻦ‪ ‬ﻫﻨﺎﻙ‪ ‬ﺍﺧﺘﻼﻓﺎﺕ‪ ‬ﻣﻌﻨﻮﻳﺔ‪ ‬ﻓﻲ‪ ‬ﻣﻌﺎﻣﻞ‪ ‬ﺍﺣﺘﺠ‪ ‬ﺎﺯ‪ ‬ﺍﻟﺮﻣ‪ ‬ﺎﺩ‪ ‬ﻭﻧﺴ‪ ‬ﺒﺔ‪ ‬ﺍﻟﻨﻴﺘ‪ ‬ﺮﻭﺟﻴﻦ‪ ‬ﻓ‪ ‬ﻲ‪ ‬ﺍﻟ‪ ‬ﺰﺭﻕ‪ ‬ﻭ‪ ‬ﺍﻟ‪ ‬ﺮﻭﺙ‪ ‬ﻭ‪ ‬ﻧﺴ‪ ‬ﺒﺔ‪ ‬ﺍﻟﻨﻴﺘ‪ ‬ﺮﻭﺟﻴﻦ‬
‫‪ ‬ﺍﻟﺘﻤﺜﻴﻠﻲ‪ ) ‬ﺍﻟﺒﻮﻝ‪ ‬ﻭ‪ ‬ﺍﻷﻧﺴﺠﺔ‪ ( ‬ﺑﻴﻦ‪ ‬ﺍﻟﻤﻌﺎﻣﻼﺕ‪ ‬ﺍﻟ‪ ‬ﺘﺠﺮﻳﺒﻴﺔ‪ . ‬ﻣﻊ‪ ‬ﻣﻼﺣﻈﺔ‪ ‬ﺃﻥ‪ ‬ﺇﺿﺎﻓﺔ‪ ‬ﺇﻧﺰﻳﻢ‪ ‬ﺍﻟﻔﻴﺘﺰ‪ ‬ﺣﺴﻦ‪ ‬ﻣﻌﻨﻮﻳﺎ‪ ‬ﻣﻦ‪ ‬ﻣﻌﺪﻝ‪ ‬ﺍﺣﺘﺠﺎﺯ‪ ‬ﺍﻟﺮﻣ‪ ‬ﺎﺩ‬
‫‪ ‬ﻭﺫﻟﻚ‪ ‬ﻋﻨﺪ‪ ‬ﻣﻘﺎﺭﻧﺘﻬﺎ‪ ‬ﺑﻤﺠﻤﻮﻋﺎﺕ‪ ‬ﻋﺪﻡ‪ ‬ﺇﺿﺎﻓﺔ‪ ‬ﺍﻷﻧﺰﻳﻢ‪ ‬ﻛﻤﺎ‪ ‬ﺃﻥ‪ ‬ﺍﻧﺨﻔﺎﺽ‪ ‬ﻣﺤﺘﻮﻯ‪ ‬ﺍﻟﻌﻠﻒ‪ ‬ﻣﻦ‪ ‬ﺍﻟﺒﺮﻭﺗﻴﻦ‪ ‬ﺍﻟﺨﺎﻡ‪ ‬ﻭ‪ ‬ﺍﻧﺨﻔﺎﺽ‪ ‬ﻣﺤﺘﻮﻯ‪ ‬ﺍﻟﻌﻠﻒ‬
‫‪ ‬ﻣ‪ ‬ﻦ‪ ‬ﺍﻟﺒ‪ ‬ﺮﻭﺗﻴﻦ‪ ‬ﺍﻟﺨ‪ ‬ﺎﻡ‪ ‬ﻭ‪ ‬ﺍﻟﻄﺎﻗ‪ ‬ﺔ‪ ‬ﺍﻟﻤﻤﺜﻠ‪ ‬ﺔ‪ ‬ﺃﺩﻯ‪ ‬ﺇﻟ‪ ‬ﻰ‪ ‬ﺍﻧﺨﻔ‪ ‬ﺎﺽ‪ ‬ﻣﻌﻨ‪ ‬ﻮﻱ‪ ‬ﻓ‪ ‬ﻲ‪ ‬ﻧﺴ‪ ‬ﺒﺔ‪ ‬ﺍﻟﻨﻴﺘ‪ ‬ﺮﻭﺟ‪ ‬ﻴﻦ‪ ‬ﻓ‪ ‬ﻲ‪ ‬ﺍﻟ‪ ‬ﺰﺭﻕ‪ ‬ﻭ‪ ‬ﺫﻟ‪ ‬ﻚ‪ ‬ﺑﺎﻟﻤﻘﺎﺭﻧ‪ ‬ﺔ‪ ‬ﺑ‪ ‬ﺎﻟﻜﻨﺘﺮﻭﻝ‬
‫‪ ‬ﺍﻻﻳﺠﺎﺑﻲ‪ ٬ ‬ﺑﻤﺎ‪ ‬ﻳﻌﻨﻲ‪ ‬ﺗﻘﻠﻴﻞ ‪ ‬ﺍﻟﺘﻠﻮﺙ‪ ‬ﺑﺎﻟﻨﺘﺮﻭﺟﻴﻦ‪ ‬ﺑﻤﻘﺪﺍﺭ ‪.% 6.7 ‬‬
‫‪ ­ 14 ‬ﺃﺩﻯ‪ ‬ﺧﻔﺾ‪ ‬ﻣﺤﺘﻮﻯ‪ ‬ﺍﻟﻌﻠﻒ‪ ‬ﻣﻦ‪ ‬ﺍﻟﺒ‪ ‬ﺮﻭﺗﻴﻦ‪ ‬ﺍﻟﺨ‪ ‬ﺎﻡ‪ ‬ﺇﻟ‪ ‬ﻰ‪ ‬ﻧﻘ‪ ‬ﺺ‪ ‬ﻣﻌﻨ‪ ‬ﻮﻱ‪ ‬ﻓ‪ ‬ﻲ‪ ‬ﻃ‪ ‬ﻮﻝ‪ ‬ﺍﻷﻣﻌ‪ ‬ﺎء‪ ‬ﻭﺫﻟ‪ ‬ﻚ‪ ‬ﻣﻘﺎﺭﻧ‪ ‬ﺔ‪ ‬ﺑﻤﺠﻤﻮﻋ‪ ‬ﻪ‪ ‬ﺍﻟﻜﻨﺘ‪ ‬ﺮﻭﻝ‬
‫‪ ‬ﺍﻹﻳﺠﺎﺑﻲ‪ ‬ﺑﻴﻨﻤﺎ‪ ‬ﻻ‪ ‬ﺗﻮﺟﺪ‪ ‬ﺍﺧﺘﻼﻓﺎﺕ‪ ‬ﻣﻌﻨﻮﻳﺔ‪ ‬ﺑﻴﻦ‪ ‬ﻣﺠﻤﻮﻋﺔ‪ ‬ﺧﻔﺾ‪ ‬ﻣﺤﺘﻮﻯ‪ ‬ﺍﻟﻌﻠ‪ ‬ﻒ‪ ‬ﻣ‪ ‬ﻦ‪ ‬ﺍﻟﺒ‪ ‬ﺮﻭﺗﻴﻦ‪ ‬ﺍﻟﺨ‪ ‬ﺎﻡ‪ ‬ﻭﺍﻟﻄﺎﻗ‪ ‬ﺔ‪ ‬ﺍﻟﻤﻤﺜﻠ‪ ‬ﺔ‪ ‬ﻋﻨ‪ ‬ﺪ‪ ‬ﻣﻘﺎﺭﻧﺘﻬ‪ ‬ﺎ‬
‫‪ ‬ﺑﻤﺠﻤﻮﻋﺔ‪ ‬ﺍﻟﻜﻨﺘﺮﻭﻝ‪ ‬ﺍﻹﻳﺠﺎﺑﻲ‪ ‬ﺃﻭ‪ ‬ﺧﻔﺾ‪ ‬ﻣﺤﺘﻮﻯ‪ ‬ﺍﻟﻌﻠﻒ‪ ‬ﻣﻦ‪ ‬ﺍﻟﺒﺮﻭﺗﻴﻦ‪ ‬ﺍﻟﺨﺎﻡ‪ ‬ﻓﻘﻂ‪. ‬‬
‫‪ ­ 15 ‬ﺃﺩﻯ‪ ‬ﺧﻔﺾ‪ ‬ﻣﺤﺘﻮﻯ‪ ‬ﺍﻟﻌﻒ‪ ‬ﻣﻦ‪ ‬ﺍﻟﺒﺮﻭﺗﻴﻦ‪ ‬ﺍﻟﺨﺎﻡ‪ ‬ﻭﺍﻟﻄﺎﻗﺔ‪ ‬ﺍﻟﻤﻤﺜﻠﺔ‪ ‬ﻣﻊ‪ ‬ﺇﺿﺎﻓﺔ‪ ‬ﺍﻟﻔﻴﺘﺰ‪ ‬ﺍﻟﻔﻄﺮﻱ‪ ‬ﺃﻭ‪ ‬ﺍﻟﺒﻜﺘﻴ‪ ‬ﺮﻱ‪ ‬ﺇﻟ‪ ‬ﻰ‪ ‬ﺍﺭﺗﻔ‪ ‬ﺎﻉ‪ ‬ﻣﻌﻨ‪ ‬ﻮﻱ‬
‫‪ ‬ﻓ‪ ‬ﻲ‪ ‬ﻧﺴ‪ ‬ﺒﺔ‪ ‬ﺩﻫ‪ ‬ﻦ‪ ‬ﺍﻟﺘﺠﻮﻳ‪ ‬ﻒ‪ ‬ﺍﻟﺒﻄﻨ‪ ‬ﻲ‪ ‬ﻋﻨ‪ ‬ﺪ‪ ‬ﻣﻘﺎﺭ‪ ‬ﻧﺘﻬ‪ ‬ﺎ‪ ‬ﺑﻤﺠﻤﻮﻋ‪ ‬ﻪ‪ ‬ﺍﻟﻜﻨﺘ‪ ‬ﺮﻭﻝ‪ ‬ﺍﻹﻳﺠ‪ ‬ﺎﺑﻲ‪ ‬ﺑﻴﻨﻤ‪ ‬ﺎ‪ ‬ﻟ‪ ‬ﻢ‪ ‬ﺗﻮﺟ‪ ‬ﺪ‪ ‬ﺃﻱ‪ ‬ﺍﺧﺘﻼﻓ‪ ‬ﺎﺕ‪ ‬ﻣﻌﻨﻮﻳ‪ ‬ﺔ‪ ‬ﺑﻴﻨﻬ‪ ‬ﺎ‪ ‬ﻭﺑ‪ ‬ﻴﻦ‬
‫‪ ‬ﻣﺠﻤﻮﻋﺔ‪ ‬ﺧﻔﺾ‪ ‬ﻣﺤﺘﻮﻱ‪ ‬ﺍﻟﻌﻠﻒ‪ ‬ﻣﻦ‪ ‬ﺍﻟﺒﺮﻭﺗﻴﻦ‪ ‬ﺍﻟﺨﺎﻡ‪ ‬ﻭ‪ ‬ﻣﺠﻤﻮﻋ‪ ‬ﺔ‪ ‬ﺧﻔ‪ ‬ﺾ‪ ‬ﻣﺤﺘ‪ ‬ﻮﻱ‪ ‬ﺍﻟﻌﻠ‪ ‬ﻒ‪ ‬ﻣ‪ ‬ﻦ‪ ‬ﺍﻟﺒ‪ ‬ﺮﻭﺗﻴﻦ‪ ‬ﺍﻟﺨ‪ ‬ﺎﻡ‪ ‬ﻭ‪ ‬ﺍﻟﻄﺎﻗ‪ ‬ﺔ‪ ‬ﺍﻟﻤﻤﺜﻠ‪ ‬ﺔ‪ ‬ﻣ‪ ‬ﻊ‬
‫‪ ‬ﺇﺿﺎﻓﺔ‪ ‬ﺍﻟﻔﻴﺘﺰ‪ ‬ﺍﻟﺒﻜﺘﻴﺮﻱ‪ ‬ﺑﻤﺎ‪ ‬ﻳﻌﻨﻲ‪ ‬ﺯﻳﺎﺩﺓ‪ ‬ﻣﻌﺪﻝ‪ ‬ﺍﻻﺳﺘﻔﺎﺩﺓ‪ ‬ﻣﻦ‪ ‬ﺍﻟﻄﺎﻗﺔ‪ ‬ﺍﻟﻤﻤﺜﻠﺔ‪. ‬‬
‫‪ ­ 16 ‬ﻟ‪ ‬ﻢ‪ ‬ﺗﻜ‪ ‬ﻦ‪ ‬ﻫﻨ‪ ‬ﺎﻙ‪ ‬ﺍﺧﺘﻼﻓ‪ ‬ﺎﺕ‪ ‬ﻣﻌﻨﻮﻳ‪ ‬ﺔ‪ ‬ﻧﺘﻴﺠ‪ ‬ﺔ‪ ‬ﺍﻟﻌﻼﺋ‪ ‬ﻖ‪ ‬ﺍﻟﺘﺠﺮﻳﺒﻴ‪ ‬ﺔ‪ ‬ﻭ‪ / ‬ﺃﻭ‪ ‬ﻧ‪ ‬ﻮﻋﻲ‪ ‬ﺍﻟﻔﻴﺘﻴ‪ ‬ﺰ‪ ‬ﺍﻟﻤﻴﻜﺮﻭﺑ‪ ‬ﻲ‪ ‬ﻓ‪ ‬ﻲ‪ ‬ﺍﻟﺘﺮﻛﻴ‪ ‬ﺐ‪ ‬ﺍﻟﻜﻴﻤ‪ ‬ﺎﻭﻱ‪ ‬ﺃﻭ‬
‫‪ ‬ﺍﻟﺼ‪ ‬ﻔﺎﺕ‪ ‬ﺍﻟﻄﺒﻴﻌﻴ‪ ‬ﺔ‪ ‬ﻟﻠﺤ‪ ‬ﻮﻡ‪ ‬ﺃﻭ‪ ‬ﺻ‪ ‬ﻔﺎﺕ‪ ‬ﺍﻟ‪ ‬ـ ‪ Tibia ‬ﺍﻟﻤﻮﻓﻮﺭﻟﻮﺟﻴ‪ ‬ﺔ‪ ) ‬ﺍﻟﻄ‪ ‬ﻮﻝ‪ ٬‬ﺍﻟﻘﻄ‪ ‬ﺮ‪ ‬ﻭ‪ ‬ﺍﻟ‪ ‬ﻮﺯﻥ‪ ( ‬ﺃﻭ‪ ‬ﺍﻟﺘﺤﻠﻴﻠﻴ‪ ‬ﺔ‪ ) ‬ﺍﻟﺮﻣ‪ ‬ﺎﺩ‪ ٬‬ﺍﻟﻜﺎﻟﺴ‪ ‬ﻴﻮﻡ‪ ‬ﻭ‬
‫‪ ‬ﺍﻟﻔﻮﺳﻔﻮﺭ‪.( ‬‬
‫‪ ­ 17 ‬ﺃﺩﻯ‪ ‬ﺇﺿﺎﻓﻪ‪ ‬ﺍﻟﻔﻴﺘ‪ ‬ﻴ‪ ‬ﺰ‪ ‬ﺍﻟﻔﻄﺮﻱ‪ ‬ﺇﻟﻰ‪ ‬ﺗﺤﺴﻦ‪ ‬ﻣﻌ‪ ‬ﻨﻮﻱ‪ ‬ﻓﻲ‪ ‬ﻣﺤﺘﻮﻯ‪ ‬ﺑﻼﺯﻣﺎ‪ ‬ﺍﻟﺪﻡ‪ ‬ﻣﻦ‪ ‬ﺍﻟﻔﻮﺳﻔﻮﺭ‪ ‬ﻭﺍﻟﻜﺎﻟﺴﻴﻮﻡ‪ ‬ﻋﻨ‪ ‬ﺪ‪ ‬ﺍﻟﻤﻘﺎﺭﻧ‪ ‬ﺔ‪ ‬ﺑﻤﺠﻤﻮﻋ‪ ‬ﻪ‬
‫‪ ‬ﻋﺪﻡ‪ ‬ﺇﺿﺎﻓﺔ‪ ‬ﺍﻟﻔﻴﺘﺰ‪ ‬ﻣﻊ‪ ‬ﻣﻼﺣﻈﺔ‪ ‬ﺃﻧﻪ‪ ‬ﻻ‪ ‬ﺗﻮﺟﺪ‪ ‬ﺍﺧﺘﻼﻓﺎﺕ‪ ‬ﻣﻌﻨﻮﻳﺔ‪ ‬ﺑﻴﻦ‪ ‬ﺍﻟﻔﻴﺘﺰ‪ ‬ﺍﻟﻔﻄﺮﻱ‪ ‬ﻭ‪ ‬ﺍﻟﺒﻜﺘﻴﺮﻱ‪ ٬‬ﻭ‪ ‬ﻟﻮ‪ ‬ﺣﻆ‪ ‬ﺯﻳﺎﺩﺓ‪ ‬ﻓﻲ‪ ‬ﻧﺸﺎﻁ‪ ‬ﺇﻧﺰﻳﻢ ‪ ‬ﺍﻟﻜﺒ‪ ‬ﺪ‬
‫‪ ALT ‬ﻧﺘﻴﺠﺔ‪ ‬ﺇﺿﺎﻓﺔ‪ ‬ﺍﻟﻔﻴﺘﻴﺰ‪ ‬ﺍﻟﺒﻜﺘﻴﺮﻱ‪٬‬ﻭ‪ ‬ﻟﻮ‪ ‬ﺣﻆ‪ ‬ﺃﻳﻀﺎ‪ ‬ﺍﻧﺨﻔﺎﺽ‪ ‬ﻓﻲ‪ ‬ﻣﺤﺘﻮﻱ‪ ‬ﺍﻟﺒﻼﺯﻣﺎ‪ ‬ﻣﻦ‪ ‬ﺍﻟﻜﻠﺴﺘﺮﻭﻝ‪ ‬ﻧﺘﻴﺠﺔ‪ ‬ﺇﺿﺎﻓﺔ ‪ ‬ﺍﻟﻔﻴﺘﻴﺰ‪ ‬ﺑﻨﻮﻋﻴﻪ‪. ‬‬
‫‪ ­ 18 ‬ﺃﺩﻯ‪ ‬ﺧﻔﺾ‪ ‬ﻣﺤﺘﻮﻯ‪ ‬ﺍﻟﻌﻠ‪ ‬ﻒ‪ ‬ﻣ‪ ‬ﻦ‪ ‬ﺍﻟﺒ‪ ‬ﺮﻭﺗﻴﻦ‪ ‬ﺍﻟﺨ‪ ‬ﺎﻡ‪ ‬ﺃﻭ‪ ‬ﺍﻟﺒ‪ ‬ﺮﻭﺗﻴﻦ‪ ‬ﺍﻟﺨ‪ ‬ﺎﻡ‪ ‬ﻣ‪ ‬ﻊ‪ ‬ﺍﻟﻄﺎﻗ‪ ‬ﺔ‪ ‬ﺍﻟﻤﻤﺜﻠ‪ ‬ﺔ‪ ‬ﺇﻟ‪ ‬ﻰ‪ ‬ﺯﻳ‪ ‬ﺎﺩﺓ‪ ‬ﻣﻌﻨﻮﻳ‪ ‬ﺔ‪ ‬ﻓ‪ ‬ﻲ‪ ‬ﺍﻻﻟﺒﻴ‪ ‬ﻮﻣﻴﻦ‬
‫‪ ‬ﻣﻘﺎﺭﻧﺔ‪ ‬ﺑﻤﺠﻤﻮﻋﺔ‪ ‬ﺍﻟﻜﻨﺘﺮﻭﻝ‪ ‬ﺍﻹﻳﺠﺎﺑﻲ‪ ٬ ‬ﺑﻴﻨﻤ‪ ‬ﺎ‪ ‬ﻟ‪ ‬ﻢ‪ ‬ﻳ‪ ‬ﺘ‪ ‬ﺄﺛﺮ‪ ‬ﻣﺤﺘ‪ ‬ﻮﻱ‪ ‬ﺑﻼﺯﻣ‪ ‬ﺎ‪ ‬ﺍﻟ‪ ‬ﺪﻡ‪ ‬ﻣ‪ ‬ﻦ‪ ‬ﺍﻟﺒ‪ ‬ﺮﻭﺗﻴﻦ‪ ‬ﺍﻟﺨ‪ ‬ﺎﻡ‪ ٬‬ﺍﻟﺠﻠﻮﺑﻴ‪ ‬ﻮﻟﻴﻦ‪ ٬‬ﻭ‪ ‬ﺍﻟ‪ ‬ﺪﻫﻮﻥ‪ ‬ﺍﻟﻜﻠﻴ‪ ‬ﺔ‪ ‬ﻭ‬
‫‪ ‬ﺍﻟﻜﻠﺴﺘﺮﻭﻝ‪ ‬ﺑﺎﻟﻤﻌﺎﻣﻼﺕ‪ ‬ﺍﻟﺘﺠﺮﺑﻴﺒﺔ‪. ‬‬
‫‪ ­ 19 ‬ﻣﻦ‪ ‬ﺍﻟﻨﺎﺣﻴﺔ‪ ‬ﺍﻻﻗﺘﺼﺎﺩﻳﺔ‪ ‬ﺳﺠﻠﺖ‪ ‬ﻋﻠﻴﻘﺔ‪ ‬ﺍﻟﻜﻨﺘﺮﻭﻝ‪ ‬ﺍﻻﻳﺠﺎﺑﻲ‪ ‬ﺃﻓﻀﻞ‪ ‬ﺩﻟﻴﻞ‪ ‬ﻟﻺﻧﺘﺎﺝ‪ ‬ﻭ‪ ‬ﺍﻟﻌﻠﻴﻘ‪ ‬ﺔ‪ ‬ﺍﻟﻤﻨﺨﻔﻀ‪ ‬ﺔ‪ ‬ﻓ‪ ‬ﻲ‪ ‬ﺍﻟﺒ‪ ‬ﺮﻭﺗﻴﻦ‪ ‬ﺍﻟﺨ‪ ‬ﺎﻡ‪ ‬ﻣ‪ ‬ﻊ‬
‫‪ ‬ﺍﻟﻄﺎﻗﺔ‪ ‬ﺍﻟﻤﻤﺜﻠﺔ‪ ‬ﺃﻓﻀﻞ‪ ‬ﻛﻔﺎءﺓ‪ ‬ﺍﻗﺘﺼﺎﺩﻳﺔ‪. ‬‬
‫‪ ‬ﻭ‪ ‬ﺧﻼﺻﺔ‪ ‬ﺍﻟﻘﻮﻝ‪ ‬ﺍﻧﻪ‪ ‬ﻳﻤﻜﻦ‪ ‬ﺗﻐﺬﻳﺔ‪ ‬ﺩﺟﺎﺝ‪ ‬ﺍﻟﺴﺎﺳﻮ‪ ‬ﻋﻠﻲ‪ ‬ﻋﻠﻒ‪ ‬ﻳﺤﺘﻮﻱ‪ ‬ﻋﻠﻲ ‪ % 20.2 ‬ﺑﺮﻭﺗ‪ ‬ﻴﻦ‪ ‬ﻣﻊ ‪ 2850 ‬ﻛﻴ‪ ‬ﻠ‪ ‬ﻮ‪ ‬ﻛﺎﻟﻮﺭﻱ‪ / ‬ﻛﺠ‪ ‬ﻢ ‪ ‬ﻋﻠ‪ ‬ﻒ‪ ‬ﻭ‬
‫‪ ‬ﺍﻟﻤﺪﻋﻢ ‪ 500 ‬ﻭﺣ‪ ‬ﺪﺓ‪ ‬ﻣ‪ ‬ﻦ‪ ‬ﺍﻹﻧ‪ ‬ﺰﻳﻢ ‪ ‬ﺍﻟﻔﻄ‪ ‬ﺮﻱ‪ ٬‬ﻓ‪ ‬ﻲ‪ ‬ﻋﻠ‪ ‬ﻒ‪ ‬ﺍﻟﺒ‪ ‬ﺎﺩﻱ‪ ‬ﻭ‪ % 19.6 ‬ﺑ‪ ‬ﺮﻭﺗﻴﻦ‪ ‬ﻣ‪ ‬ﻊ ‪ 3092 ‬ﻛﻴﻠ‪ ‬ﻮ‪ ‬ﻛ‪ ‬ﺎﻟﻮﺭﻱ‪ / ‬ﻛﺠ‪ ‬ﻢ ‪ ‬ﻋﻠ‪ ‬ﻒ‪ ‬ﻓ‪ ‬ﻲ ‪ ‬ﻋﻠ‪ ‬ﻒ‬
‫‪ ‬ﺍﻟﻨﺎﻣﻲ‪ ٬ ‬ﻭ ‪ % 17 ‬ﺑﺮﻭﺗﻴﻦ‪ ‬ﻣﻊ ‪ 3023 ‬ﻛﻴﻠﻮ‪ ‬ﻛﺎﻟﻮﺭﻱ‪ / ‬ﻛﺠﻢ‪ ‬ﻋﻠﻒ‪ ‬ﻭﺍﻟﻤﺪﻋﻢ ‪ 500 ‬ﻭﺣ‪ ‬ﺪﺓ‪ ‬ﻣ‪ ‬ﻦ‪ ‬ﺇﻧ‪ ‬ﺰﻳﻢ‪ ‬ﺍﻟﻔﻴﺘﻴ‪ ‬ﺰ‪ ‬ﺍﻟﻔﻄ‪ ‬ﺮﻱ‪ ‬ﻓ‪ ‬ﻲ‪ ‬ﻋﻠ‪ ‬ﻒ‪ ‬ﺍﻟﻨ‪ ‬ﺎﻫﻲ‬
‫‪ ‬ﻟﻠﺤﺼﻮﻝ‪ ‬ﻋﻠﻲ‪ ‬ﺃﻓﻀﻞ‪ ‬ﻣﻌﺪﻝ‪ ‬ﻟﻠﺘﺤﻮﻳﻞ‪ ‬ﺍﻟﻐﺬﺍﺋﻲ‪ ٬‬ﻭ‪ ‬ﻟﻜﻦ‪ ‬ﻣﻦ‪ ‬ﺍﻟﻨﺎﺣﻴﺔ‪ ‬ﺍﻻﻗﺘﺼﺎﺩﻳﺔ‪ ‬ﺳﺠﻠﺖ‪ ‬ﻋﻠﻴﻘﺔ‪ ‬ﺍﻟﻜﻨﺘﺮﻭﻝ‪ ‬ﺃﻓﻀﻞ‪ ‬ﺩﻟﻴﻞ‪ ‬ﻟﻺﻧﺘﺎﺝ‪ ‬ﻭ‪ ‬ﺍﻟﻌﻠﻴﻘ‪ ‬ﺔ‬
‫‪ ‬ﺍﻟﻤﻨﺨﻔﻀﺔ‪ ‬ﻓﻲ‪ ‬ﺍﻟﺒﺮﻭﺗﻴﻦ‪ ‬ﺍﻟﺨﺎﻡ‪ ‬ﻣﻊ‪ ‬ﺍﻟﻄﺎﻗﺔ‪ ‬ﺍﻟﻤﻤﺜﻠﺔ‪ ‬ﺃﻓﻀﻞ‪ ‬ﻛﻔﺎءﺓ‪ ‬ﺍﻗﺘﺼﺎﺩﻳﺔ‪.‬‬
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