GSM`s 2005 Scottish Terrier Health Survey

GSM’s 2005 Scottish Terrier
Health Survey
Epidemiology Baselines
For The Scottish Terrier Population
Joseph Harvill, Ph.D.,
Publisher/Editor, Great Scots Magazine
T
he anticipated results are in from the GSM Scottish Terrier Health Survey distributed in the March/
April 2005 issue of Great Scots Magazine. This study is important in the world of Scotties since it encompasses for the first time the Scottie population at-large, including the non-show-dog population of
pet Scotties and their homes who were not surveyed in 1995 when the Scottish Terrier Club of America (STCA) did
its in-house health survey of showring breeders. Hence, this data represents the most comprehensive look at Scottish
Terrier demographics, health, and longevity in the 105 years of our breed’s history.
In this first of a series of planned surveys I had two broad objectives as goals: to gather demographics on the
modern Scottish Terrier, where they are concentrated geographically, the characteristics of their home environments,
and profile the typical Scottie owner, including where and in what numbers companion owners acquire their dogs.
The second broad objective for this first survey was to establish morbidity and mortality baselines for the modern
Scottish Terrier population at-large.
In addition, a special research question emerged from the data, viz., is there a correlation between Scottish
Terrier health problems and the source of their breeding, in other words, how do ‘well-bred’ Scottish Terrier disease
ratios compare to pet store dogs? Our data revealed surprising answers.
A word about our population sample and ‘typicality.’ Our sample consisted of 506 hard copy surveys (22%
return rate) encompassing records of 902 deceased Scotties and 785 living Scotties for a total of 1687 dogs. This is
not, strictly speaking, a random sample of the total Scottish Terrier population alive today, it is a cross-section of the
Scottie lover population who read Great Scots Magazine. A look at what the survey reveals as to fastidious care and
money spent annually on Scotties might be construed as evidence against typicality across the total existing population. That said, it is important to bear in mind two things with reference to representativeness: first, although sample
representativeness is a key to generalizable numbers, so is sample size because statistical probability is a product of
large numbers. Since this is the largest dataset ever collected on the Scottie population at-large it reflects the fullest
cross-section look at the health and well-being of the modern Scottish Terrier. But second, and more important with
reference to representativeness, is the fact that bias, if present in this sample, is toward supererogatory pet healthcare,
and therefore presumably, toward healthier dogs. It is possible, in other words, that Scottie health outside this sample is
worse than revealed here; it is not likely it is better. This conclusion is strengthened by the unusual care demonstrated
in the filling out of forms as evidenced by self-consistency overall within survey answers and remarkably low rate of
anomalies, by the careful and thorough delineation of Scottie diseases by layman pet owners, and by the substantial
amounts of money spent on healthcare—all of these inspire confidence that this survey population is exemplary of
high levels of responsible dog ownership, indeed, of Scottie ownership at its best. Therefore, this data, based as it is
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2005 GSM Scottie Health Sur vey
on a best case scenario for the care and maintenence of the modern Scottish Terrier, is even more compelling in its
revelation of breed-wide health and longevity problems in Scotties.
The 2005 GSM Scottish Terrier Health Survey, therefore, is an important benchmark toward an accurate health
assessment of the breed.
I. Methodology & Observations
The methodology used in the survey analysis included four different types of statistical tests: Analysis of Variance (ANOVA), Chi-Square, two sample t-tests, and difference of proportion tests. For each analysis of variables in
the survey a P-Value (probability) is attached in the full published report which in general is an estimate of the probability that the observed differences between groups are due to naturally occurring random variation and not because
other factors are causing them. In short, high P-Values indicate no significant differences; low P-Value (under 5%)
indicates the differences are statistically significant.
These are elemental, bread and butter statistical tools, nothing exotic, since the purpose of this survey was to
get simple but accurate baseline measures on the Scottie population as a whole. But it is just these kinds of elemental
tabulations and averages which are the foundation of epidemiology, and just these kinds of basic statistics which
have been missing in our breed’s history.
Observations
The first observation I wish to make in reporting this research project is that it turned out a ‘clean’ study. This is
by no means always the case. Statisticians use ‘clean’ to reference data that is nonambiguous and self-commensurate.
The GSM survey was clean in the sense that it involved straightforward, elemental statistics; clean in the sense the
form was easy to understand; clean in the sense the forms were fully filled out with great care and detail; clean in
the sense there were few answer anomalies; clean in the sense that the data entry stage had few anomalies; clean in
the sense the final numbers and tabulations are unambiguous and clear.
The second observation is the impressive cameo of human-canine bonding that emerges from this survey—a
group remarkably devoted to dogs at remarkably high risk. These are long-termers, with an average of 20.1 years
of Scottie companionship who spent an average of $492 last year per dog on Scottie medical bills—and 12.9% of
whom spent between $1000-$5000. The high cost of Scotties is clear: almost half of all deaths (48.4%) are due to
cancer and the expense of cancer treatments quickly drain even robust bank accounts. These numbers mean one out
of two Scottie owners will battle Scottie cancers. In addition, our high-cost Scottie companions so fiercely loved and
expensed are short-lived, living an average of only 10.15 years. Such devotion despite high costs and high mortality
is remarkable.
The third general observation from this research is the clear evidence here that Scottish Terrier health risks and
issues are breed wide. Careful attention was given in the analysis to segregate Scotties according to their reported
source of origin, i.e., professional breeder, newspaper ad, rescue, pet store, to allow comparative health analysis. PValues in all the tests were high, indicating there were no significant differences in health across the groups. Whether
Scotties are ‘well-bred’ or otherwise, on average their morbidity is the same and medical costs are the same, with
the non-professionally bred Scottie owners spending an average of $36 less last year ($473 compared to $510). This
evidence contradicts the received wisdom that a Scottie from a show breeder assures better health and fewer medical
bills. Furthermore, this data shows our health problems cannot be attributed to puppy mills since show dogs manifest the same health risks on average as pet store Scotties, indicating a Scottie gene pool thoroughly homogenous
in terms of morbidity.
The fourth observation to come out of this research project is that the big issue facing our breed is longevity.
Cancer is the number 1 killer of Scotties (48.4% of reported deaths), but lack of genetic fitness as vouchsafed by
longevity is the underlying health issue. The modern Scottish Terrier’s immune system is not coping and his lifespan
shows it. The Scottie’s average lifespan of 10.15 years is not commensurate with other small breeds. Both Westies and
Cairns, to name but two close canine cousins, exceed the Scottie average by at least half, the Cairn Terrier boasting
numbers closer to 20. Actual empirical canine longevity studies are less common than anecdotal claims and inflated
guesses and this is especially true in Scottish Terrier circles. Claims of “13 – 14 years” are made routinely but without
empirical evidence. Indeed, the GSM survey is the first attempt at a breed-wide assessment of Scottie mortality and
the numbers are not encouraging. I say that because the evidence shows that a person buying a professionally bred
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2005 GSM Scottie Health Sur vey
Figure 1
Scottish Terrier is twice as likely to have that well-bred
dog die at two years of age as they are to have that
Scottie live to be 16. Almost 1 in three (29%) will die
before their ninth birthday, 36% never make it to ten,
and fully half of well-bred Scottie owners will bury
their Scottie soon after a 10th birthday (10.15 years
average age at death). More alarming, however, is
evidence that the Scottish Terrier lifespan is shrinking.
Comparison of the GSM average age at death (10.15
years) against the STCA’s 1995 survey numbers (11.2
years) suggests the breed has lost a tenth of its lifespan
in the past decade. The STCA’s 1995 average age at
death numbers may not be accurate (the sample size
was small and included only show breeders, raising plausibility of ‘dirty’ data whereby respondents
have vested interest in underreporting disease and
overstating longevity). However, the 1995 data is the
closest thing we have to a prior empirical longevity
report, and so taking it at its face value it indicates
the longevity trend is going down, not up, for the
Scottish Terrier. This is an alarming
trend—a tenth of the lifespan lost in
a decade—and may signal the rapid
declension in a gene pool which can
happen when inbreeding depression
reaches critical mass in a small, closed
population. Improving genetic health
of the Scottish Terrier through breeding for longevity appears to be job #1
for tomorrow’s responsible breeders.
Figure 2
II. Cameo of the Modern Scottie
World
The emergent prof ile of the
modern Scottish Terrier’s owner and
home is noteworthy. 506 homes were
surveyed, obtaining records on 785
living Scotties and records on 902
deceased Scotties, for a total of 1687
dogs. Geographic distribution clusters
as follows: one in five live in the South
(20.0%), followed closely by the Great
Lakes region (18.6%), the Pacific
(16.4%), and Mid-Atlantic (14.4%),
Great Plains (7.7%), Mountain (7.1%),
South Central (Texas, etc.) (6.9%),
New England (6.7%), and various
international locations with minimal
numbers (see Figure 1). Our survey
Scotties live in homes (not apartments)
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2005 GSM Scottie Health Sur vey
(89.3%), a slight majority live in cities above 50,000 population (40.5%), but a third of the total are in rural homes
(30.4%). These Scottie homes are stable, evidenced in the fact the average years in residence is 16.6 years.
Just over half of the sample homes have only one Scottie (51.4%), they are predominantly two-person households (69.2%) in the age range 50-69 (60.0%), nearly half are professionals (46.8%) and a third are retired (31.2%).
Average respondent’s years of Scottie experience is 20.1 years and reported levels of Scottie involvement include
show breeders (7.7%) who are involved in the STCA, some as regional club board members and/or newsletter editors.
18.0% of survey respondents list involvement with Scottie Rescue, and 7.7% are involved in other activities such
as agility, obedience training, or going to ground. Two-thirds of surveyed Scotties have not had formal obedience
training (65.7%).
Ratio of Scottie coat colors are as follows (1% not responding): Black (66.4%), Brindle (21.5%), Wheaten
(11.2%). This coat color baseline will be important to track as ‘fad’ indicator for future breeding trends.
Surveyed Scotties share their home with other pets ranging from birds to horses to turtles: cats (69.1%), birds
(13%), other dog breeds (26%), among which the breed of choice is Westhighland White Terriers (23.6%).
As discussed above, the average Scottie medical bill last year was $492 (see Figure 2).
Of special interest is survey data on
Figure 3
origins of companion Scotties enabling us to
Origin Deceased
Origin Living
answer for the first time the questions, where
Scotties
Scotties
do pet people get their dogs and in what ratios?
AKC estimates that as few as 5% of purebred
dogs are bred by breed clubs, which, if true
of Scotties, predicts that 95% of our dogs
would come from non-professional sources.
Our survey data shows a very different picture
among Scottie owners: of the currently living
dogs reported, over half were obtained from
a professional breeder (52%), 13.9% through
newspaper ads, 17.7% through Scottie Rescue,
6.7% from a pet store, 9.7% from other sources
(a friend who died, etc.). What this shows, as
discussed earlier, is that the sample population of Scotties surveyed cannot be dismissed
as junkyard dogs with health problems due to
bad breeding. The sample is a cross-section of show bred Scotties, backyard bred Scotties, and pet store/puppy mill
dogs, with the solid majority being ‘well-bred,’ and therefore health problems and short lifespan data documented
by this survey cut evenly across the entire Scottie population, and therefore confirm endemic genetic problems in
the breed.
Of special note is comparison of gains and losses with respect to Scottie sourcing (see Figure 3). Figure 3
charts sources for deceased and also for living Scotties. The two charts represent a rough approximation of ‘before’
and ‘after’ snapshots affording glimpses at trends across time in Scottie buying. Using the survey’s average Scottie
longevity of 10.15 years, the two charts may be conjectured as a decade of change in buying habits. Notice that purchases of puppies from pet stores is down by half, from 13.6% to today’s 6.7%, and that buying from a professional
breeder is up 14.2%, from 38.8% to today’s 52.0%. Buying out of the newspaper is down 7.1% and rehoming a
Scottie through Scottie Rescue is up 5.1%. Now this approximated time period coincides with the publication span
of GSM and may reflect amelioration effects of magazine advocacy for responsible breeding and buying. Whether
attributable to magazine influence or not the sourcing trends are notable.
As indicated above, this portrait of Scotties and their people is noteworthy in its detail and scope. What emerges
for this publisher is new awareness of how remarkable the Scottie community is in their unstinting devotion to dogs
who are high-cost and high-risk companions.
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2005 GSM Scottie Health Sur vey
Figure 4
III. Scottish Terrier Health Picture
The meat of the 2005 GSM Scottish Terrier Health Survey is its statistical
baselines for health and longevity in today’s Scottie.
For the 902 deceased Scotties reported, a total of 916 causes of death
were reported, indicating that a few respondents listed more than a single health
issue as cause of death.
Figure 5
All reported causes were
included in the analysis.
Reported Causes of Death
with Cancer Categories
Each cause was grouped
into one of six general
categories.
Repor ted causes
of death identify cancer
as the number 1 killer
of Scotties (48.4%) (see
Figure 4). Diseases or
failures of organs such
as kidneys or heart were the second most common cause of
death (18.4%). The endocrine system category includes death
attributed to Cushing’s and thyroid diseases (6.0%). The ‘age’
category refers to dogs reported to have died of old age (5.2%)
and it is notable that so few Scotties are perceived as living long
enough to merit this cause of death.
Another category of note in the reported causes of Scottie
deaths is the ‘accidental’ death category (8.7%). This includes
deaths by traffic accidents, eating bones and poisons, etc.,
all of which are to some degree preventable. This is a higher
percentage of Scottie deaths than is attributed to old age and
speaks to opportunities for increased owner vigilance as a way
to contribute to increased Scottish Terrier longevity.
Types of cancers reported were broken out to enable visualization of the range of cancer problems Scotties are facing
(see Figure 5). Bladder cancer is the most frequently specified
cancer (11.6%), with liver and lymph cancers each at 5.6%
of the reported causes of death. Interestingly, oral cancer is
reported as cause of 1.2% of deaths and it is being targeted by
the STCA for research funds while liver and lymph cancers
which have six times higher incidence rate in Scotties, are not
yet targeted.
Health problems reported in living Scotties were similarly
grouped into the same six categories as the reported causes
of death. It is instructive to lay out the percentages of these
six categories of health problems reported in professionally
bred Scotties next to the percentages reported in non-professionally bred Scotties (see Figure 6). Note the occurrences
are not dramatically different but the chart shows small differences worth noting. Allergies are reported 1 in every five
Rescue Scotties (20.4%), but occur 6.6% less frequently in
professionally bred Scotties (13.8%). It is generally taken for
Cause of Death
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2005 GSM Scottie Health Sur vey
Figure 6
Scottie Health By Origin
granted that show breeders’ dogs will not have skin problems
(Scottie coat is a significant portion of showring points), so the
pro breeders’ lower allergy incidences confirms the attention to
coat and skin problems expected, although it is notable that the
data show their dogs are not free of allergies. Endocrine system
problems are a different story: 6.1% reported in newspaper ad
Scotties compared to 23.6% reported in professionally bred
dogs—17.5% difference. This category encompasses thyroid and Cushing’s Disease and suggests an aspect of Scottish Terrier health that deserves to be researched. Genetically, it appears the non-professionally bred dogs among us
have healthier Endocrine Systems.
Figure 7
Special attention was devoted in the analysis to deComparison of Average Age At Death
termine if Scottie sources of origin significantly influence
By Origin
health/longevity. In other words, do ‘well-bred’ dogs, for
example, have fewer diseases and live longer than Rescue
Scotties or dogs from pet stores? An Analysis of Variance
(ANOVA) was performed to see if there were any significant differences between the average ages at the time of
death in the Scotties from different origins. The P-Value
was high (22.3%: to be statistically significant the p-value
requires to be below 5%) indicating not enough evidence
to say the differences are other than naturally occurring
variances across the gene pool.
Figure 8
As can be seen in Figure 7, the data form an esAverage Age At Death By
sentially flat longevity line across all Scotties regardless
Professional/Non-Professional Origin
of breeding origin with a slight edge in the average age
at death for Rescue Scotties. When the four groups of
origin are collapsed into two categories of ‘professional
breeder’ and ‘non-professional breeder’ the average age
at death is virtually identical (see Figure 8).
To give a clearer breakout of ages at death in Scotties, histograms were created to display the distributions
of ages at death for the four categories of Scottie source/
origin (see Figure 9, p. 12). Comparison of the four histograms reveals essentially the same distribution pattern,
all with negative skew, meaning a bell-curve stretched out
with a tail to the left. This long tail to the left represents
Scottie deaths at young ages and it is this skew that pulls
down the average for Scottie longevity.
Although the distribution patterns in the four histograms are little different, indicating there is no appreciable
difference in the average age at death across the four types of Scottie origin, closer examination of the charts is
instructive. Our predicament over Scottish Terrier longevity is made poignant by looking at the histogram of ages at
death for professionally bred Scotties (see: Figure 9 top graph)—which ostensibly are the best dogs among us. Notice twice as many professionally bred Scotties die at two years of age as die at 16. Fully 29%—almost 1 in 3—die
before their 9th birthday and 36% of professionally bred Scotties die before their 10th birthday. On average, only four
out of 10 professionally bred Scotties make it into their 12th year.
A glance at the other three histograms which chart the ages at death for the other categories of Scottie origin,
which include Rescue Scotties, pet store dogs, and Scotties bought out of the newspaper, turns up other interesting
mortality data in the modern Scottish Terrier. Each of the them records Scotties reaching 19 years, including Rescues—a two year lifespan greater than the oldest professionally bred Scottie in the survey.
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2005 GSM Scottie Health Sur vey
Figure 9
Professionally Bred Scotties: Distribution of Ages at Death
The important point to take
away from the survey mortality data,
however, is the essentially flat line
sameness in longevity averages across
professionally bred and non-professionally bred Scotties. The evidence
does not support claims that ‘wellbred’ dogs are healthier or live longer.
The empirical evidence indicates that
the best shot—even if a long shot—at
a long-lived Scottie is from a nonprofessional breeder.
In Figure 10 (p. 13) the average
Non-Professionally Bred Scotties: Distribution of Ages at Death
age at death by the cause of death is
graphed. This information suggests
genetic ‘walls’ our dogs are hitting
with reference to certain diseases. On
average, the 10th year is a grim cancer
year for our dogs, endocrine breakdown associates with the 11th year, as
also organ system failure (11th year).
Such late-onset diseases are clear evidence of lack of genetic fitness in our
breed since no one who loves Scotties
Newspaper/Other Bred Scotties: Distribution of Ages at Death
would argue that 10 or 11 years of
age is appropriate for bodily system
breakdown in a small dog.
One additional factor in modern
Scottish Terrier health calls for comment. The data consistently identify
Rescue Scotties as having more health
problems. In Figure 11, Rescue dogs
are shown on average to have 8.7%
more health problems (38.8% reported with problems) than professionally
Rescue Scotties: Distribution of Ages at Death
bred Scotties (30.1% reported problems). In the demographic section of
the full published report you can find
a corresponding record of greater
medical expenses for Rescue Scotties.
This finding is consistent with the fact
that problems precipitate surrender of
dogs to the Rescue program by owners
lacking the will or the means to cope.
Therefore, by definition Scotties coming into rehoming situations reflect
problems and they are adopted in full recognition of their special needs. More striking, however, than the health and
expenses data for Scottie Rescues, and illustrated in Figure 12 which charts percent of Scotties with health conditions by professional/non-professional origin, is that empirical evidence shows well-bred Scotties on average are a
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2005 GSM Scottie Health Sur vey
Figure 10
Average Age at Death by Cause of Death
Figure 11
Percent of Scotties with Health
Conditions By Origin
Figure 12
Percent of Health Problems By
Professional/Non-Professional Origin
mere 2.8% healthier than non-professionally bred Scotties.
Common parlance treats pet store and backyard bred dogs as
synonymous with puppy mills, ill health and bad breeding, yet
actual Scottie numbers disprove that assumption. Given higher
prices demanded for Scotties bred by show breeders and claims
of excellence it might be expected there would be greater differential in average percentage of health problems between the
two groups. At the very least, this evidence suggests ‘well-bred’
in current usage is in need of redefinition.
In summary, longevity and the genetic fitness which it presupposes, are the key issues facing the modern Scottish Terrier
in the 2005 GSM Scottish Terrier Health Survey. Cancer is
the number one killer of our dogs. The morbidity data gathered
here shows health problems are breed-wide cutting across all
categories of puppy production contributing to short-lived dogs without the ‘good genes’ for longevity. Bladder Cancer is the most frequently cited cause of Scottie death by cancer in the GSM survey (11.6% of deaths), confirming
Purdue University’s research on bladder cancer which found incidence of bladder cancer in the Scottish Terrier at 18
times the rate occurring in the canine population at-large. At the very least this convergence of data suggests genetic
predisposition toward Bladder Cancer in the Scottish Terrier (and may be indicative of other predispositions) and is
another piece of evidence for the health predicament of the modern Scottish Terrier.
Conclusions
This first breed-wide look at Scottish Terrier epidemiology is not encouraging for the health and well-being of
the breed. Rates of morbidity and mortality are alarmingly high and they are the same across the entire population
without significant difference by source of breeding from show dog to puppy mill Scottie, suggesting that our health
problems may be more endemic than is easily manipulable through changing breeding techniques.
Underlying today’s short-lived Scotties appears to be impaired immunity and lack of general genetic fitness
as manifested in the breed’s susceptibility (and even predisposition) to cancers. The survey shows cancer now kills
48.4% of our dogs—one out of two. It is tempting to hope we might help at least half of our dogs to a longer life
if we selectively bred Scotties toward a healthier immune system to combat cancers. Elsewhere I have raised the
troubling issue of inbreeding’s harmful impact on immunity, referencing the important recent findings at University
of California, Davis, which for the first time analyzed with 100 microsatellite markers the canine genome’s Major
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2005 GSM Scottie Health Sur vey
Histocompatibility Complex (MHC), best known for its role in the immune system (see: GSM, Nov/Dec 2003). Genetic diversity is crucial at the MHC site because the more genetically diverse the site, the wider the immunologic
response the individual is capable of mounting, and the more duplicate genes at the MHC site the narrower range of
response an individual can mount when challenged immunologically. The UCDavis microsatellite marker research
is a brilliant, hard-evidence look at how inbreeding produces animals that acquire the same genes from both parents
as a result of their common ancestry, and so acquire less diverse and therefore less efficient and effective immune
systems. Line breeding, in other words, stacks the genetic cards against the purebred dog because it impairs natural
resistance and survival in a pathogenic world.
The 2005 GSM Scottish Terrier Health Survey is a baseline look at breed-wide manifestations of impaired
resistance and survival in the Scottish Terrier. While the endemic nature of health problems across all Scotties in
the gene pool may render breeding out our problems difficult and maybe impossible, it is now more important than
ever to practice breeding as genetic conservationists by carefully monitoring inbreeding coefficients (COI) to lower
kinship ratios across the gene pool and so move our breed toward more genetic diversity as a way to boost natural
immunity and so help our dogs toward relative hybrid vigor.
Our dogs’ health problems are expensive—average health costs alone last year were $492 per dog, and that
says nothing of grooming and feeding. Cancer is the big killer, taking one out of two Scotties (48.4%), and cancer
diagnosis and treatment costs are crippling. Worse, our survey shows the companions we love are short-lived. When
comparison is made to the STCA’s 1995 survey of average Scottie lifespan of 11.2 years, this survey’s 2005 breedwide data showing average age at death of 10.15 years indicates an alarming downward trend—the breed has lost a
year, or roughly a tenth, of its average lifespan in a decade.
The Scottish Terrier breed is in trouble, as this health survey sample shows in detail. Breed leaders have practiced a century of breeding without a health registry by which to track health and longevity trends with the result
that we face breed-wide health peril today. Denial will not save the dogs we love nor help those who pay the bills
and bury the dead.
It’s time for honesty and action. It has been said that morality is the way we would like the world to be, whereas
economics is the way the world actually is. This baseline 2005 survey of the demographics and epidemiology of the
Scottish Terrier may not be the picture we would like it to be, but it is empirical evidence of how matters actually are
in the world of the modern Scottie. Economist Steven D. Levitt reminds us all that beyond debates over pragmatics,
hard numbers keep us grounded. “It is well and good to opine or theorize about a subject, as humankind is wont to
do, but when moral posturing is replaced by an honest assessment of the data, the result is often a new, surprising
insight” (Steven D. Levitt, Freakonomics, 2005).
It is hoped that an honest assessment of these data may result in new and surprising insights that will help the
plight of the Scottish Terrier.
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