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33
A STUDY ON EFFECT OF AGE, BREED AND SEX ON
BLOOD SUGAR LEVEL OF DISEASED DOGS
Research Article
Shibabrata Pattanayak1, Subashis Batabyal*2, Amlan Patra3
ABSTRACT: A study was conducted on the dogs with moderate to serious illness coming for treatment
at the Dog Ward of West Bengal University of Animal and Fishery Sciences, West Bengal, India, to
find out possible correlation between fasting blood sugar level with breed, sex and age of dogs. The
study result implicated that the blood sugar level was not having any general tendency to increase
with advancement of age of ailing dogs. The blood sugar level of ailing dogs was higher in small
breeds of dogs, particularly in 0 to <4 year age group. The large breeds showed highest level of sugar
in blood in disease condition at above the age 12 years or more. The blood sugar level of ailing dogs
had a gender bias, as it was found more in females than males in all breeds and age groups.
INTRODUCTION
The ailing dogs arriving to the hospitals with
moderate to severe level of illness are expected
to have different blood sugar level than normal
dogs. In one side, infections in the body can
drive blood sugar levels high. On the other hand,
dogs with moderate and severe level of disease
may not eat food sufficiently, so the fasting
animals may have a reduced level of blood
sugar. It was postulated that infections or
diseased conditions can modify blood sugar
levels, which may be due to pancreatitis
resulting inability to produce insulin
(www.petmed.com./dog/high blood sugar),
influence of change of intestinal microflora
(Akerblom et al., 2002). The gut immune
system likely plays a central role in the
pathogenesis of type 1 diabetes, because
accumulating evidence suggests that the
manifestation of autoimmune diabetes can be
modifed by factors which influence the gut
immune system. (Vaarala 1999). The gut and
the pancreas are probably immunologically as
well as anatomically linked and influenced by
environmental factors such as intestinal
microflora, infections and dietary factors. The
1 Assistant Director, ARD (Microbiology), Institute of Animal Health & Veterinary Biologicals (R&T),
37, Belgachia Road, Kolkata - 700037,West Bengal, India.
2 Associate Professor and Head, Department of Biochemistry, West Bengal University of Animal &
Fishery Sciences, 37, Belgachia Road, Kolkata- 700037,West Bengal, India.
3 Department of Animal Nutrition, West Bengal University of Animal & Fishery Sciences, 37, Belgachia
Road, Kolkata - 700037, West Bengal, India.
*Corresponding author. e-mail: batabyals2009@gmail.com
Explor Anim Med Res,
Vol.4, Issue - 1, 2014, p. 33-43 ISSN 2277- 470X (Print), ISSN 2319-247X (Online)
Website: www.animalmedicalresearch.org
Key Words: Dog, Blood sugar, Disease.
34
Exploratory Animal and Medical Research, Vol.4, Issue 1, June, 2014
environmental risk factors that are frequently
implicated in type 1 diabetes are enteroviral
infections and exposure to cow’s milk proteins,
both trigger the gut immune systems (Akerblom
et al., 2002).
Although extensive pancreatic damage is
responsible for the development of diabetes in
28% of diabetic dogs, evidence of acute or
chronic pancreatitis is found in a larger
proportion (40%) of diabetic dogs. Obesity
affects one quarter to one third of dogs
presented to veterinary practices (Mason 1970,
Anderson 1973, Edney and Smith 1986) and is
associated with increased risk of pancreatitis
(Hess et al., 1999). As pancreatitis appears to
be a common cause of diabetes in dogs
(Alejandro et al., 1988), this relationship
between obesity and pancreatitis in dogs has
relevance to the pathogenesis of canine diabetes
(Rand et al., 2004). The majority of diabetic
dogs appear to have a form of type 1 diabetes
analogous to the latent auto-immune diabetes
of adults (LADA) in humans ( Fleeman and
Rand 2001). At least 50% of diabetic dogs
would be classified as type 1, because this
proportion has been shown to have antibodies
against beta cells (Hoenig and Dawe 1992, Elie
and Hoenig 1995, Davison et al., 2003) The
remainder probably has ‘other specific types of
diabetes’ resulting from pancreatic destruction
or chronic insulin resistance, or they have
diestrus-induced diabetes (Rand et al., 2004).
The prevalence of diabetes in dogs has been
estimated to be 0.32% in the UK (Catchpole et
al., 2005). The prevalence of canine diabetes
has been estimated to be anywhere between
0.0005% and 1.5% (Catchpole et al., 2005).
It is hypothesized that chronic ingestion of a
high-carbohydrate diet promotes obesity and
increases the demand on β-cells for insulin
secretion, thereby predisposing individuals to
hyper insulinemia, apoptosis, β-cell failure, and
development of diabetes (Porte 1991). The
present study was planned to study whether
there is any effect of age, breed and sex on the
blood sugar level of dogs in disease conditions.
No dogs with any previous report of chronically
suffering of Diabetes Mellitus were included
in our study.
MATERIALS AND METHODS
Animals: The study was performed on the
dogs (Canis familiaris) arrieved for treatment
during the period of August 2011 to January
2014 in the Dog Ward of West Bengal
University of Animal and Fishery Sciences,
Kolkata, West Bengal, India with serious illness.
The study was performed on 323 dogs. Dogs
with no disease or with minute ailments were
excluded from the study.
Procedures: Blood samples from the ailing
dogs coming for treatment were obtained for
estimation of blood glucose level. Glucose was
estimated by using GOD-POD method
described by Trinder (1969) using commercially
available Glucose Test Kit (Span Diagnostics
Limited, India). In the test, glucose oxidase
oxidizes glucose present in the serum samples
to gluconic acid and hydrogen peroxide. In
presence of enzyme peroxidase, released
hydrogen peroxide is coupled with phenol and
4 – amino antipyrine to form colored
quinoneimine dye. Absorbance of colored dye
was measured at 505 nm and it is directly
proportional to glucose concentration in the
serum samples tested.
Study Parameters:
1 . Study of effect of age
For statistical analysis, dogs were grouped
35
into four age groups: 0 to <4 years, 4 years to
<8 years, 8 years to <12 years and ≥12 years.
Then the data analysis was performed to
observe the effect of age on all types of ailing
dogs, on male and female dogs and also on
different breed types of dogs.
2. Study of effect of breed type of dog
The dogs were classified into small, medium
and large sized breed dogs. Small breed group
included Pug, Lhasa Apso, Pomeranian,
Dachshund, Chihuahua and Spitz. Medium
breed group included Labrador, Rottweiler,
Cocker Spaniel, Golden Retriever, Beagle,
Whippet, Dalmatian and Mongril, while large
breed group included Alsetian, German
Shepherd, Doberman Pinscher, Great Dane and
Iris setter.
Then data analysis was performed on small,
medium and large dog groups at all ages and
also on small, medium and large dogs separately
at different age groups.
3. Study of effect of gender
This study was performed by observing the
comparative effect of males and females as a
whole as well as separately at each age group.
The breed, age and sex of the ailing dogs
were noted along with fasting blood sugar level.
The collected raw data was analyzed using SAS
(1999). Least square mean values of blood sugar
have been presented in the Tables.
RESULT AND DISCUSSION
From our study, it appears that there is no
direct detectable correlation between age and
blood sugar level of ailing dogs (Table 1). But
if we proceed towards detail analysis, some very
interesting trends come out. In overall breed
type analysis, the mean values for small,
Age (years)
0 to <4 years
4 to <8 years
8 to <12 years
≥≥
≥≥
≥12 years
Breed type
Small
Medium
Large
Gender
Male
Female
Mean Value
96.85
101.78
89.10
99.73
105.60
95.24
81.68
86.10
104.56
Standard Error
8.07
6.16
7.76
10.71
6.41
5.36
10.79
6.08
4.92
No.of observation
65
112
104
42
116
166
41
128
195
P-value
0.63
0.14
0.019
Table 1: Effect of overall age, breed type and gender of ailing dogs on blood sugar (mg/dl).
A study on effect of age, breed and sex on blood sugar level of diseased dogs.
36
Exploratory Animal and Medical Research, Vol.4, Issue 1, June, 2014
medium and large breed of dog were 105.60,
95.24 and 81.68 mg/dl, respectively, but the
statistical effect was 0.14. It may be due to high
variation in the range of data with standard error
of 10.79 in the large breed of dogs (Table 1).
The smaller breeds had a tendency to have
higher blood sugar than medium breeds, and
medium breeds had same tendency than the
large breeds of dogs in disease condition.
A statistically significant effect (P=0.019)
was found on the effect of sex on blood sugar
level of diseased dogs. The female dogs had a
mean value is 104.56 in contrast to the mean
blood sugar of 86.10 for male dogs (Table 1).
In the detail group based analysis, in the age
group of 0 to <4 years, a significant effect
(P=0.056) was observed for sex with the mean
values of 80.66 and 109.88 for male and female,
respectively (Table 3). The same tendency was
found in 8 to <12 years age group (P = 0.10,
sugar levels of 79.94 and 104.06 for male and
female, respectively) (Table 3). The difference
was not significant but wide for the age group
of 12 years and more (male 89.06 and female
105.67) (Table 3), but such large difference was
not found in 4 to <8 years group (93.88 and
99.61mg/dl. for male and female, respectively)
(Table 3).
A highly significant effect (P= 0.0097) was
observed in the blood sugar level among the
breeds of dogs in 0 to <4 years of age group.
The estimated values of least squire means for
Table 2: Effect of breed type in the different age groups of ailing dogs on blood sugar
(mg/dl).
0 to <4 years
Small
Medium
Large
4 to <8 years
Small
Medium
Large
8 to <12 years
Small
Medium
Large
≥≥
≥≥
≥12 years
Small
Medium
Large
Mean Value
135.21
85.34
74.66
93.18
101.38
71.44
104.14
92.00
77.95
97.24
89.40
158.33
Standard Error
14.30
9.19
20.77
14.57
7.59
22.78
10.56
12.50
16.53
11.49
19.58
35.75
No.of observation
16
40
09
22
81
09
49
35
20
29
10
03
P-value
0.0097
0.43
0.39
0.23
37
small, medium and large breed of dogs of this
age group were 135.21, 85.34 and 74.66,
respectively (Table 2). Though not significant
(P= 0.39), but the same type of decreasing
tendency was also found in the 8 to <12 years
age group with mean values of 104.14, 92.00
and 77.95 for small, medium and large breed
of dogs, respectively (Table 2). But in the 4 to
<8 years age group, the blood sugar level of
small breeds was more than large breeds, but
Gender Mean Value Standard Error No.of observation P-value
0 to <4 years
Male 80.66 11.21 30 0.056
Female 109.88 10.06 35
4 to <8 years
Male 93.88 10.32 44 0.66
Female 99.61 8.30 68
8 to <12 years
Male 79.94 11.74 39 0.10
Female 104.06 9.09 65
≥≥
≥≥
≥ 12 years
Male 89.06 16.25 15 0.41
Female 105.67 12.11 27
Table 3: Effect of gender in the different age groups of ailing dogs on blood sugar
(mg/dl).
Table 4: Effect of age of the males and females ailing dogs on blood sugar (mg/dl).
Mean Value Standard Error No.of observation P-value
Male
0 to <4 years 80.66 7.36 31 0.64
4 to <8 years 91.54 6.10 44
8 to <12 years 82.15 7.47 39
≥≥
≥≥
≥12 years 89.06 10.92 15
Female
0 to <4 years 135.21 18.85 16 0.76
4 to <8 years 100.17 15.26 22
8 to <12 years 101.44 13.16 49
≥≥
≥≥
≥12 years 97.24 15.26 29
A study on effect of age, breed and sex on blood sugar level of diseased dogs.
38
Exploratory Animal and Medical Research, Vol.4, Issue 1, June, 2014
medium sized breeds showed highest level of
blood sugar (93.18, 101.38 and 71.44 for small,
medium and large breeds, respectively)
(Table 2). Interestingly, in the highest range of
age (12 years and above), the result was
opposite. The medium breeds had lowest level
of sugar followed by small breeds and then large
breeds (small 97.24, medium 89.40 and large
158.33). In that age group, the large breed of
ailing dogs showed a high level of blood sugar
(mean value was 158.33) (Table 2).
It was observed that among the large breeds
of dogs, the blood sugar level increased with
advancement of age (P= 0.0034), and
particularly above 8 years of age. The mean
values were 74.66, 71.47, 80.71 and 158.33 for
0 to <4, 4 to <8, 8 to <12, and 12 and more
ages, respectively (Table 5). But among the
small breeds, the mean value was highest in
0 to <4 age group and then decreased (135.21,
100.17, 101.44, and 97.24) (Table 5). On the
other hand, the highest value was found in the
4 to <8 years age group among the medium
sized breeds (107.82) (Table 5).
A very little number of reports of systematic
study on blood sugar of dogs are available, and
study on blood sugar level of ailing dogs is
scanty. So our study report may be compared
with the previous studies related with canine
diabetes. It is reported that diabetes typically
occurs in dogs between 5 and 12 years of age,
with a median age of 9 years, illustrating that
canine diabetes is generally a disease of middle-
aged and older dogs (Catchpole et al., 2005).
In a study for insurance claim for dog diabetes,
it was found that the mean age at 1st insurance
claim for the diabetic dogs was 8.6 years (Tove
Fall et al., 2007).
Mean Value Standard Error No.of observation P-value
Small breeds
0 to <4 years 135.21 18.85 16 0.39
4 to <8 years 100.17 15.26 22
8 to <12 years 101.44 13.16 49
≥≥
≥≥
≥12 years 97.24 15.26 29
Medium breeds
0 to <4 years 85.34 9.40 40 0.077
4 to <8 years 107.82 7.00 81
8 to <12 years 75.62 12.27 35
≥≥
≥≥
≥12 years 89.40 20.17 10
Large breeds
0 to <4 years 74.66 11.56 09 0.0034
4 to <8 years 71.46 8.95 15
8 to <12 years 80.71 9.27 14
≥≥
≥≥
≥12 years 158.33 20.03 03
Table 5: Effect of age of the different breed types of ailing dog on blood sugar (mg/dl).
39
Fig.1: Effect of overall age of ailing dogs on blood sugar (mg/dl).
Fig.2: Effect of breed type of ailing dogs on blood sugar (mg/dl).
In our study, we did not find any such
correlation of increase level of blood sugar in
middle or older aged ailing dogs as a whole
(Table 1 and Fig.1), but the highest level of
blood sugar was found in the 0 to <4 year age
group among small sized dogs (mean value
135.21), 4 to <8 year age group among middle
sized dogs (mean value 107.82) and 12 years
A study on effect of age, breed and sex on blood sugar level of diseased dogs.
40
Exploratory Animal and Medical Research, Vol.4, Issue 1, June, 2014
Fig.3: Effect of gender of ailing dogs on blood sugar (mg/dl).
Fig.4: Effect of breed type in different age groups of ailing dogs on blood sugar (mg/dl).
and above age group among large sized dogs
(mean value 158.33). (Table 5).
Though female ailing dogs showed a
tendency of having higher level of blood sugar
irrespective of age than male (Table 4), the study
reveals that dogs, as a species, failed to show
any significant effect of age on blood sugar
level during illness (Table 1). This result did
not correlate the previous study performed on
dogs for identification of diabetes, as stated
≥≥
≥≥
≥
41
earlier. Small type of dogs showed higher level
of blood sugar at 0 to <4 year of age group in
our study (Table 5), but according to the
previous reports juvenile onset of diabetes is
not common in dogs (Catchpole et al., 2005)
though most of the cases of diabetes in dog is
due to Type 1 diabetes with antibodies against
beta cells (Rand et al., 2004).
In previous reports of study on canine
diabetes, breed of dogs is considered as a
predisposing factor for diabetes (Catchpole
et al., 2013). Breeds predisposed to diabetes
include the Samoyeds, Tibetan Terrier and Cairn
Terrier (Catchpole et al., 2008), Australian
Terriers, Swedish Elkhounds, and Swedish
Lapphunds (Tove Fall et al., 2007), Miniature
Schnauzers, Miniature Poodles, Pugs, Toy
Poodles (Hess et al.,2000), Beagles,
Dachshunds (www. petmed.com, High blood
sugar in dogs 2013), Cocker Spaniel,
Keeshounds (Ehow.com, Signs of
hyperglycemia in dogs 2013).
Boxer, German Shepherd and Golden
Retriever dogs are likely to be less susceptible
(Catchpole et al., 2008). Diabetes is seen
infrequently in Cocker Spaniels, Shepherds and
Collies, (http://www.diabetes.co.uk/info/
DogsWithDiabetes.htm 2013), Cavalier King,
Charles Spaniel, Doberman, Jack Russell
Terrier, Labrador Retriever, Mixed Breed,
Rottweiler, West Highland Terrier (Wikipedia
Diabetes in dogs 2013).
Breed differences in susceptibility to diabetes
mellitus in dogs suggest an underlying genetic
component to the pathogenesis of the disease
and associations were found with three specific
haplotypes. This haplotype is common in
diabetes-prone breeds (Samoyed, Cairn terrier
and Tibetan terrier) but rare in diabetes resistant
breeds (Boxer, German shepherd and Golden
retriever), which could explain differences in
the prevalence of diabetes in these different
Fig.5: Effect of gender of ailing dogs of different age groups on blood sugar (mg/dl).
≥≥
≥≥
≥
A study on effect of age, breed and sex on blood sugar level of diseased dogs.
42
Exploratory Animal and Medical Research, Vol.4, Issue 1, June, 2014
breeds (Catchpole et al., 2008). Diabetes
mellitus in dogs has been associated with major
histocompatibility complex (MHC) class II
genes (dog leucocyte antigen; DLA), with
similar haplotypes and genotypes being
identified in the most susceptible breeds
(Catchpole et al., 2013).
The blood sugar pattern of ailing dogs has
some levels of similarity with previous reports
of dog diabetes study where differences in
breeds have effect on susceptibility to diabetes
(Catchpole et al., 2013). The dog breeds with
small sized body showed highest level of sugar
in blood followed by medium and then large
sized dogs as a whole (Fig. 2) as well as in the
0 to -<4 year age group (Fig. 4).
Effect of gender among diabetic dogs was
different in different studies. Among the
diabetic dogs, females were 72% in a study
(Tove Fall et al., 2007), but it was reported 53%
in another study (Catchpole et al., 2005). It was
also reported that the proportion of females with
diabetes varied significantly among breeds.
Dogs of Swedish Elkhound, Beagle, Norwegian
Elkhound, and Border Collie breeds that
developed diabetes were almost exclusively
females (Tove Fall et al., 2007). In our study,
the female ailing dogs showed higher level of
blood sugar as a whole (Fig.3) as well as in
different age groups (Fig.5).
CONCLUSION
From our study, it was revealed that the blood
sugar level of ailing dogs was higher in small
breeds of dogs, particularly in 0 to <4 year age
group. The large breeds showed highest level
of sugar in blood in disease condition at the
age of 12 years or more. The blood sugar level
of ailing dogs was found more in females than
males in all breeds and age groups.
ACKNOWLEDGEMENT
The authors acknowledge the Vice
Chancellor, West Bengal University of Animal
and Fishery Sciences, West Bengal, India for
providing necessary facilities for the study
related with this article.
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*Cite this article as: Pattanayak S, Batabyal S, Patra A (2014) A study on effect of age, breed
and sex on blood sugar level of diseased dogs. Explor Anim Med Res 4(1): 33-43.
A study on effect of age, breed and sex on blood sugar level of diseased dogs.
