Effect of Length of Ensiling on Nutrient Content of

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Effect of Length of Ensiling on Nutrient Content of
Effect of Length of Ensiling on
Nutrient Content of Corn Silage and
it’s Impact on Ration Balancing
Luis C. Solórzano, Ph. D., Dipl. ACAS
Director of Technical Services, James Farrell & Co.
Adjunct Faculty, University of Puerto Rico
Overview
 Corn silage is corn silage, why all the fuzz?
 Nutritional changes during storage
 Consequences of these changes
 Adjusting diets
 Recommendations
Corn silage is corn silage
 Traditionally, once corn is harvested and ensiled
it is assumed that it becomes stable and ready
for feed-out within 6-8 weeks
 In reality, most dairymen do not wait that long
to start feeding corn silage post ensiling
 New research suggests that we may need to
store corn silage >6 mo to optimize it’s feeding
The Ensiling Process
Phase I
Phase II
Aerobic
Phase
Anaerobic
Phase
Phase III
Phase IV
Continued
Stable Phase
Anaerobic Phase
Phase V
Feedout Phase
Active
Microorganisms
Plant Enzymes,
Aerobic
Microorganisms
Acetic Acid
Bacteria,
Lactic Acid
Bacteria
Lactic Acid
Bacteria
Lactic Acid
Bacteria
Molds, Yeasts
Activity
Production of
CO2, Water,
and Heat
Production of
Acetic Acid,
Lactic Acid,
Alcohols, and
Production of
Lactic Acid
Production of
Lactic Acid
Aerobic
Deterioration
CO2
pH
6.5
Temperature
69oF
5.0
4.5
90oF
2
84oF
3
Days After Ensiling
21
7.0
The Ensiling Process
 Consumes water soluble carbohydrates (WSC) resulting in
the production of:
 CO2
 Water
 Heat
 Organic acids
 Alcohols
 Many times, other undesirable compounds (eg. amines)
 Resulting in significant changes in the proportions of
nutrients available in the stored corn silage
 Also, nutrient digestibility may change during storage
DM and sugar content corn silage ensiled for 0,
240 or 385 d
Length of ensiling, d
Item
DM, %
Sugar (WSC), %
Fresh crop
36.7a,b
240
39.9a
385
27.05b
8.7a
1.79b
1.67b
Solórzano et al., 2015
Take home message
The crop that is ensiled is
different from the silage that is
eventually fed to cattle
If we feed 10 kg silage as fed, without taking
into account changes in DM%
3,55
3,5
3,45
Corn Silage DM offered, kg/d
3,4
3,35
3,3
3,25
3,2
3,15
3,1
3,05
3
1
2
3
4
5
6
7
8
9
Day
10
11
12
13
14
15
16
If we do not take into account silage
DM%
Daily DMI may fluctuate significantly. In this
example, upwards of 0.31 kg/hd/d
This has negative consequences on animal
health and productivity
Acidosis-diarrhea
Foot health
Low milk fat content
Diarrhea/loose
stools
Low milk production and
milk components
Foot problems and lameness
Let’s make it a bit more complex…
Let’s consider what happens when both, DM
and CP fluctuate in the silage being fed…
CP offered from 10 kg as fed of corn
silage
300,00
CP offered from 10 Kg aas fed of corn silage, g/d
290,00
280,00
270,00
260,00
250,00
240,00
230,00
1
2
3
4
5
6
7
8
9
Day
10
11
12
13
14
15
16
CP offered from 10 kg as fed of corn
silage
May fluctuate upwards of 50 g/hd/d from corn silage
alone
And…
we spend money on by-pass proteins, protected amino
acids and other expensive ingredients: eg. blood meal,
fish meal.
Take home message
Control the basics:
Monitor DM content of forages on a daily basis
and adjust rations accordingly
How about starch from corn silage?
The primary reason for feeding corn silage is
it’s the content of fiber and starch
We continue to learn about this key
ingredient…
DM, starch and sugar content of corn silage
ensiled for 0, 240 or 385 d
Length of ensiling, d
Item
DM1, %
Starch, %
Sugar (WSC), %
Fresh Crop
36.7a,b
240
39.9a
385
27.05b
42.9a
37.38a
34.39a
8.7a
1.79b
1.67b
Changes in nutrient content of corn
silage
So, if corn silage changes in DM content, has
less sugars and starch content, how come it
feeds better the longer it is ensiled?
The answer may be in the changes of
the digestibility of starch
DM, starch content, and starch digestibility of
corn silage ensiled for 0, 240 or 385 d
Length of ensiling, d
Item
DM1, %
Fresh crop
36.7a,b
240
39.9a
385
27.05b
Starch, %
42.9a
37.38a
34.39a
7 hr. In Situ ruminal starch
digestibility, % starch
65.4b
90.72a
87.97a
 After 8 months of ensiling, starch
digestibility increases more than 25
percentage units!!
DM, starch content, starch digestibility and
starch supply from corn silage ensiled for 0, 240
or 385 d
Length of ensiling, d
Item
DM1, %
Fresh crop
36.7a,b
240
39.9a
385
27.05b
Starch, %
42.9a
37.38a
34.39a
7 hr. In Situ ruminal starch
digestibility, % starch
65.4b
90.72a
87.97a
Starch supplied by 10 kg DM of
corn silage
4.29a
3.74a
3.44a
Digestible starch supplied by 10
kg DM of corn silage
2.80a
3.39a
3.03a
Why the drastic increase in starch
digestibility?
Hoffman et al, 2011
+
Intensity
Prior to Ensiling
Ensiled 240 d
Duration
++
--
Starch digestibility
 Non-starch components, such as the protein
matrix, which binds starch granules together,
may limit attack by microbes and enzymes, thus
decreasing starch digestion (Owens et al., 1986).
 The degree of starch encapsulation by zein at
ensiling combined with fermentation intensity
and length of the fermentation (LOF) appear to
regulate the disassociation of starch granule
(Hoffman et al., 2011)
 The changes in starch digestibility
are equivalent to feeding an
additional 820 g/hd/d of ground
corn!!
And nothing as done to the ration!
Impact on ration balancing
Ration balancing must be performed based
on the changing nutritional characteristics
and nutrient digestion kinetics of ensiled
forages
Failure to do so will result in:
Lower cow performance
Diminished cow health
Negative economic impacts on the farm
Recommendations for silage analysis
Item
Frequency
Where?
Action
DM content
Daily
On farm
Adjust diets daily
CP, starch, fiber
Weekly-Monthly
Laboratory
(NIR)
Adjust diets based
on most recent
results
Minerals
Monthly
(main concern are
close up cows)
Laboratory
(Wet Chemistry)
Adjust diets based
on most recent
results
Fermentation
profile
At least monthly
Laboratory (NIR
OK, Wet Chemistry
preferred)
Make decisions
regarding silage
management
Fiber and starch
Digestibility
Monthly-Quarterly
Laboratory
(In Vitro or In Situ)
Adjust diets based
on most recent
results
(cost is a concern)
Thank you!!!
[email protected]

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