Non-dietary risk factors for gastric dilatation-volvulus in large and giant breed dogs

OBJECTIVE: To identify non-dietary risk factors for gastric dilatation-volvulus (GDV) in large breed and giant breed dogs. DESIGN: Prospective cohort study. ANIMALS: 1,637 dogs > or = 6 months old of the following breeds: Akita, Bloodhound, Collie, Great Dane, Irish Setter, Irish Wolfhound, Newfoundland, Rottweiler, Saint Bernard, Standard Poodle, and Weimaraner. PROCEDURE: Owners of dogs that did not have a history of GDV were recruited at dog shows, and the dog's length and height and the depth and width of its thorax and abdomen were measured. Information concerning the dog's medical history, genetic background, personality, and diet was obtained from the owners, and owners were contacted by mail and telephone at approximately 1-year intervals to determine whether dogs had developed GDV or died. Incidence of GDV, calculated on the basis of dog-years at risk for dogs that were or were not exposed to potential risk factors, was used to calculate the relative risk of GDV. RESULTS AND CLINICAL RELEVANCE: Cumulative incidence of GDV during the study was 6% for large breed and giant breed dogs. Factors significantly associated with an increased risk of GDV were increasing age, having a first-degree relative with a history of GDV, having a faster speed of eating, and having a raised feeding bowl. Approximately 20 and 52% of cases of GDV among the large breed and giant breed dogs, respectively, were attributed to having a raised feed bowl.     

Incidence of and breed-related risk factors for gastric dilatation-volvulus in dogs

OBJECTIVE: To compare incidence of and breed-related risk factors for gastric dilatation-volvulus (GDV) among 11 dog breeds (Akita, Bloodhound, Collie, Great Dane, Irish Setter, Irish Wolfhound, Newfoundland, Rottweiler, Saint Bernard, Standard Poodle, and Weimaraner). DESIGN: Prospective cohort study. ANIMALS: 1,914 dogs. PROCEDURE: Owners of dogs that did not have a history of GDV were recruited at dog shows, and the dog's length and height and depth and width of the thorax and abdomen were measured. Information concerning the dogs' medical history, genetic background, personality, and diet was obtained from owners, and owners were contacted by mail and telephone at approximately 1-year intervals to determine whether dogs had developed GDV or died. Incidence of GDV based on the number of dog-years at risk was calculated for each breed, and breed-related risk factors were identified. RESULTS AND CLINICAL RELEVANCE: Incidence of GDV for the 7 large (23 to 45 kg [50 to 99 lb]) and 4 giant (> 45 kg [> 99 lb]) breeds was 23 and 26 cases/1,000 dog-years at risk, respectively. Of the 105 dogs that developed GDV, 30 (28.6%) died. Incidence of GDV increased with increasing age. Cumulative incidence of GDV was 5.7% for all breeds. The only breed-specific characteristic significantly associated with a decreased incidence of GDV was an owner-perceived personality trait of happiness.     

Mortality and morbidity due to gastric dilatation-volvulus syndrome in pedigree dogs in the UK

Objectives : To estimate breed-specific risk of death due to, and prevalence of, gastric dilatation-volvulus (GDV) in UK pedigree dogs. Methods : Data were available on the reported cause of and age at death and occurrence of and age at diagnosis of disease from the 2004 purebred dog health survey. A total of 15,881 dogs of 165 breeds had died in the previous 10 years; GDV was the cause of death in 65 breeds. There were 36,006 live dogs of 169 breeds of which 48 breeds had experienced ≥1 episodes of GDV. Prevalence ratios were used to estimate breed-specific GDV mortality and morbidity risks. Results : Gastric dilatation-volvulus was the cause of death for 389 dogs, representing 2.5% (95% CI: 2.2-2.7) of all deaths reported and the median age at death was 7.92 years. There were 253 episodes in 238 live dogs. The median age at first diagnosis was five years. Breeds at greatest risk of GDV mortality were the bloodhound, Grand Bleu de Gascogne, German longhaired pointer and Neapolitan mastiff. Breeds at greatest risk of GDV morbidity were the Grand Bleu de Gascogne, bloodhound, otterhound, Irish setter and Weimaraner. Clinical Significance : These results suggest that 16 breeds, mainly large/giant, are at increased risk of morbidity/mortality due to GDV.     

Comparison of two canine registry databases on the prevalence of hip dysplasia by breed and the relationship of dysplasia with body weight and height

OBJECTIVE: To compare the results of 2 canine registries for classification of the hip joints for dysplasia by breed, and to relate the percentage of dysplastic dogs with body metric characteristics. SAMPLE POPULATION: Data on the ranking order of hip dysplasia by breed from 2 registries for 156 dog breeds. PROCEDURES: The prevalence of hip dysplasia listed by the Orthopedic Foundation for Animals (OFA) and the breed mean score according to the list of the British Veterinary Association (BVA) Kennel Club Hip Dysplasia scheme were related to weight and height as well as the body mass index (BMI; kg/m(2)) by breed. RESULTS: The OFA ranking order and the percentage of dysplastic dogs were highly correlated with the BVA mean score (rho = 0.74). A significant correlation was found between the prevalence of hip dysplasia and the BMI (r = 0.63). Receiver operating characteristic curve analysis revealed that the highest area under the curve, corresponding to the best discrimination, was at a BMI of 110 kg/m(2) with a criterion value of 15% dysplastic dogs (area under the curve, 0.89). Because the ratio of dogs in the positive and negative groups reflected the prevalence of the condition among breeds in the OFA database, the positive likelihood ratio was 9.32 and the negative likelihood ratio was 0.24. CONCLUSION AND CLINICAL RELEVANCE: The OFA statistics and the BVA mean scores reflected the prevalence of hip dysplasia among dog breeds. Body mass index accurately discriminated between breeds with high or low prevalence of hip dysplasia.     

Association of breed with the diagnosis of congenital portosystemic shunts in dogs: 2,400 cases (1980-2002)

OBJECTIVE: To determine the annual and overall proportion of diagnoses of congenital portosystemic shunts (CPSS) in dogs and identify breeds at increased risk for CPSS. DESIGN: Retrospective study. ANIMALS: 2,400 dogs with CPSS from veterinary teaching hospitals that reported to the Veterinary Medical Database (VMDB) from January 1, 1980 to February 28, 2002. PROCEDURE: The proportion of diagnoses of CPSS was calculated for all dogs and each breed recorded in the VMDB annually and for the 22.2-year period. Odds ratios and adjusted confidence intervals were calculated for breeds with at least 100 accessions by comparing odds of each breed with a diagnosis of CPSS with that of mixed-breed dogs. RESULTS: Congenital portosystemic shunts were reported in 0.18% of all dogs and 0.05% of mixed-breed dogs. The proportion of diagnoses of CPSS increased from 5 in 10,000 dogs in 1980 to 5 in 1,000 dogs in 2001. Yorkshire Terriers had the greatest total number of diagnoses of CPSS. Thirty-three breeds were significantly more likely to have a diagnosis of CPSS, compared with mixed-breed dogs. The greatest proportions of diagnoses were found in Havanese (3.2%), Yorkshire Terriers (2.9%), Maltese (1.6%), Dandie Dinmont Terriers (1.6%), and Pugs (1.3%). CONCLUSIONS AND CLINICAL RELEVANCE: Certain breeds appear to be at increased risk for CPSS, compared with mixed-breed dogs. The increased odds ratios among specific breeds support the hypothesis of a genetic predisposition for CPSS. Clients and veterinarians should consider appropriate diagnostic tests for dogs with clinical signs and those used for breeding from breeds with increased risk of CPSS.     

Breed predisposition to congenital alacrima in dogs

Objective  To evaluate the clinical characteristics and breed predisposition of congenital alacrima in dogs.
Animals studied  Dogs with congenital keratoconjunctivitis sicca.
Procedures  A search of the medical records of the University of Tennessee Veterinary Teaching Hospital from 1974–2005 and the University of California–Davis Veterinary Teaching Hospital from 1986–2006 for dogs under 1 year of age with a diagnosis of keratoconjunctivitis sicca (KCS) was performed. These cases were further reviewed for dogs with a Schirmer's tear test I of ≤ 5 mm/min before 6 months of age, with no known causes for KCS, which did not respond to appropriate KCS therapy; these cases were considered to have congenital alacrima. These breeds were compared to all other breeds using the Fisher's exact test with correction for multiple comparisons.
Results  Congenital alacrima was identified in 19 dogs representing 11 breeds and mixed breeds. Yorkshire Terriers and Bedlington Terriers were statistically overrepresented compared to reference populations ( P  < 0.01 and P  = 0.04, respectively).
Conclusions  Yorkshire terriers are significantly at risk for congenital alacrima compared to other breeds. The significance of the increase in congenital alacrima in Bedlington Terriers in this study may not be clinically relevant and may be due to the small total number of dogs of this breed that presented to the both hospitals. Based on the poor response to therapy in humans with congenital alacrima, it may be prudent to offer guarded prognoses for KCS in juvenile Yorkshire terriers.     

A Retrospective Study of Conservative Treatment of Gastric Dilatation-Volvulus in the Dog

A retrospective study of 103 dogs with gastric dilatation-volvulus (GDV) treated conservatively during the period 1985–1989 was performed. The date and number of recurrences, and the date and cause of death along with breed, age and sex were collected from clinic records and from a questionnaire sent to the owners (77% response). The treatment consisted of emptying the stomach with a stomach tube, gastrocentesis if necessary and treating shock.All of the affected dogs were from moderate to large sized breeds and the study showed that particular breeds appear to be predisposed to GDV. The average age was 7.2 years and there was no gender predisposition. Sixty-six per cent of the dogs survived the initial treatment and 50% of the dogs were still alive 1 month after treatment. Thirty-nine dogs (71%) received recurrence between 5–760 days after initial treatment. Fifty-six per cent had recurrence within 3 months and all except 2 dogs, within 1 year. Data for the time of death, regardless of cause, was available for 68 dogs. Of these 59 (81% ) died within a year after initial treatment. Conservative treatment was found to be an adequate life-saving procedure in the acute stage of GDV, but could not alone prevent recurrence of the disease.     

RELATIONSHIP OF CERVICAL SPINAL CORD DIAMETER TO VERTEBRAL DIMENSIONS: A RADIOGRAPHIC STUDY OF NORMAL DOGS

Cervical spinal cord abnormalities are often unapparent on myelographic studies, because no normal values for cervical spinal cord diameter are currently available. The purpose of this study was to establish, myelographically, the normal sagittal diameter of the cervical spinal cord in large and small breed dogs and its relationship to the sagittal diameter of the vertebral canal and sagittal height/length of the corresponding vertebral bodies. Forty-one adult dogs underwent cervical radiography and myelography. Spinal cord and vertebral canal sagittal diameter, vertebral body height at C2 to 5, body length at C3 to 5, and dorsal spine length of C2 were measured on lateral views. Ratios of spinal cord:vertebral canal diameter, spinal cord:body height, and spinal cord:body length/spine were calculated, and a normal range was determined for small and large breed dogs. The spinal cord:vertebral canal ratios showed that small breeds have a higher cervical cord-to-canal ratio than large breeds. The mean values and ranges of 14 ratios are reported. The ratios of spinal cord:body length at C2 to 4 in small breeds and spinal cord:body height at C3 to 5 in large breeds were found to be the most accurate for assessing spinal cord sagittal diameter. These normal ranges would allow quantitative and objective evaluation of the cervical spinal cord by myelography and early identification of dogs with altered spinal cord diameter, which could be further evaluated by means of alternative imaging techniques.     

X-ray and CT morphology of atlas variants in the dog

To investigate variations in atlas shape in dogs the image archives of the Department for Small Animals and Horses, University of Vienna, and The Royal Veterinary College, University of London were searched for radiographs and CT images of the canine atlas. 32 radiographic and 78 CT studies, including 51 toy and 54 large breed dogs, were retrieved and analysed. Five dogs had both radiographs and CT scans. Patients with pathologic alterations, such as fractures and incomplete ossification of the atlas, as well as oblique projections were excluded. Compared to large breed dogs (body weight more than 30 kg) the atlas of toy breed dogs (body weight less than 10 kg) had a reduced craniocaudal and an increased dorsoventral diameter. The vertebral longitudinal axis appeared to be dorsorotated, resulting in a steeper rise of the atlas wings and a more dorsally located lateral vertebral foramen. When comparing the atlas of toy and large breed dogs, the distribution of three morphologic parameters was statistically different: Ratio length to height (toy breeds > 1, large breeds < or = 1), shape of the vertebral chanal (toy breeds: vertically oval, large breeds: round resp. cross-oval, or vertically oval) and trabecular bone of the dorsal arch (toy breeds: absent, large breeds: present). There was no significant difference in the morphology of the ventral arch. Differences in atlas morphology could contribute to the predisposition of toy breed dogs to atlanto-axial instability; however, further studies are necessary to test this hypothesis.     

Gastric emptying of nondigestible radiopaque markers after circumcostal gastropexy in clinically normal dogs and dogs with gastric dilatation-volvulus.

Using radiopaque particles mixed with food, gastric emptying was assessed in healthy dogs not subjected to surgery, in healthy dogs 9 to 35 days after circumcostal gastropexy, and, in dogs 1 to 54 months after surgical treatment and recovery from gastric dilatation-volvulus (GDV). Circumcostal gastropexy surgery did not alter the 90% gastric emptying time for radiopaque particles in healthy dogs. However, 90% gastric emptying time was significantly (P less than 0.05) increased after circumcostal gastropexy in dogs with GDV, compared with healthy dogs after the same surgical procedure and recovery period. These results imply that dogs with GDV have delayed gastric emptying of solid particles. Whether delayed gastric emptying of markers detected in affected dogs after surgical treatment and recovery was the result or the cause of GDV was not determined. Results indicate that circumcostal gastropexy could be recommended as a prophylactic procedure for GDV in large breeds with deep thorax, because delayed gastric emptying of markers secondary to the surgical procedure is unlikely.     

RADIOGRAPHIC LIVER SIZE IN PEKINGESE DOGS VERSUS OTHER DOG BREEDS

Differential diagnoses for canine liver disease are commonly based on radiographic estimates of liver size, however little has been published on breed variations. Aims of this study were to describe normal radiographic liver size in Pekingese dogs and to compare normal measurements for this breed with other dog breeds and Pekingese dogs with liver disease. Liver measurements were compared for clinically normal Pekingese (n = 61), normal non‐Pekingese brachycephalic (n = 45), normal nonbrachycephalic (n = 71), and Pekingese breed dogs with liver disease (n = 22). For each dog, body weight, liver length, T11 vertebral length, thoracic depth, and thoracic width were measured on right lateral and ventrodorsal abdominal radiographs. Liver volume was calculated using a formula and ratios of liver length/T11 vertebral length and liver volume/body weight ratio were determined. Normal Pekingese dogs had a significantly smaller liver volume/body weight ratio (16.73 ± 5.67, P < 0.05) than normal non‐Pekingese brachycephalic breed dogs (19.54 ± 5.03) and normal nonbrachycephalic breed dogs (18.72 ± 6.52). The liver length/T11 vertebral length ratio in normal Pekingese (4.64 ± 0.65) was significantly smaller than normal non‐Pekingese brachycephalic breed dogs (5.16 ± 0.74) and normal nonbrachycephalic breed dogs (5.40 ± 0.74). Ratios of liver volume/body weight and liver length/T11 vertebral length in normal Pekingese were significantly different from Pekingese with liver diseases (P < 0.05). Findings supported our hypothesis that Pekingese dogs have a smaller normal radiographic liver size than other breeds. We recommend using 4.64× the length of the T11 vertebra as a radiographic criterion for normal liver length in Pekingese dogs.     

Climatic conditions as a risk factor in canine gastric dilatation-volvulus

Canine acute gastric dilatation-volvulus (GDV) is a life-threatening condition of multifactorial origin. The risk of developing GDV is influenced by a variety of factors, including breed, age, gender, temperament, diet and management. A relationship between seasonal variations and the frequency of GDV has been previously documented although no association was found with any specific climatic event. Variables in weather conditions within a defined geographic region were investigated in a retrospective study of 287 client-owned dogs diagnosed with GDV between 1992 and 1999. Monthly incidences were evaluated and differences in atmospheric temperature, humidity and pressure between days in which GDV cases were observed and days in which no case was presented were examined. Although temperature was significantly associated with the occurrence of GDV, the difference in temperatures between days with and days without GDV cases was so small that it is unlikely to be of clinical relevance. Moreover, no significant association was found between GDV occurrence and atmospheric pressure or humidity, and a seasonal variation in GDV incidence was not observed.     

Prevalence of and risk factors for leptospirosis among dogs in the United States and Canada: 677 cases (1970-1998)

OBJECTIVE: To determine whether there was a temporal trend in prevalence of leptospirosis among dogs in the United States and Canada and to determine whether age, sex, and breed were risk factors for the disease. DESIGN: Retrospective study. ANIMALS: 1,819,792 dogs examined at 22 veterinary teaching hospitals between 1970 and 1998. PROCEDURES: The Veterinary Medical Data Base was searched for records of dogs in which a diagnosis of leptospirosis was made, and hospital prevalence was calculated. Logistic regression was used to examine the association between leptospirosis and age, sex, and breed. RESULTS: 677 dogs with leptospirosis were identified. Thus, hospital prevalence was 37 cases/100,000 dogs examined. A significant increase in leptospirosis prevalence between 1983 and 1998 was identified. Male dogs were at significantly greater risk of leptospirosis than were female dogs; dogs between 4 and 6.9 years old and between 7 and 10 years old were at significantly greater risk than dogs < 1 year old; and herding dogs, hounds, working dogs, and mixed-breed dogs were at significantly greater risk than companion dogs. CONCLUSIONS AND CLINICAL RELEVANCE: The prevalence of leptospirosis among dogs examined at veterinary teaching hospitals in the United States and Canada has increased significantly since 1983. Male dogs of working and herding breeds were at greater risk.     

Breed-specific pro-inflammatory cytokine production as a predisposing factor for susceptibility to sepsis in the dog

Objective: To determine whether 2 dog breeds with a high risk for parvoviral enteritis, a disease associated with sepsis, produce stronger pro‐inflammatory cytokine responses to a stimulus than dogs with a lower risk. Design: Blinded comparison. Setting: University outpatient clinic. Animals: Healthy, unrelated, purebred Doberman Pinschers (n=10) and Rottweilers (n=9) with age‐matched mixed‐breed dogs (n=7). Interventions: Heparinized, whole‐blood samples were collected from each dog and incubated for 6 hours with lipopolysaccharide. Plasma was collected, and bioassays were used to determine the concentrations of TNF‐α and IL‐6. The mean values obtained from the high‐risk breeds were compared with the mean obtained from the mixed‐breeds. Measurements and main results: The mean TNF‐α production from dogs with a high risk for parvoviral enteritis (1321±161 pg/mL; Doberman Pinscher and Rottweiler) was greater (P<0.05) than that from lower risk, mixed‐breed dogs (674±186 pg/mL). There were no differences in TNF‐α levels between Doberman (1128±247 pg/mL) and Rottweiler (1563±pg/mL) breeds or between any breeds with regard to IL‐6 production. Conclusions: The magnitude of TNF‐α production by peripheral blood monocytes was the greatest in the dogs with breed‐related risk for parvoviral enteritis. However, additional studies are needed to prove a causal relationship between high TNF and predilection for parvoviral enteritis. Regardless, breed appears to be a predisposing factor for variations in cytokine production that could impact the host response to infection and other inflammatory insults.     

Canine gastric dilatation-volvulus

Gastric dilatation-volvulus (GDV) is a dramatic and enigmatic disease of large and giant breed dogs characterised by the rapid accumulation of gas in the stomach. This causes gastric dilatation, twisting of the stomach about its long axis, compression of surrounding organs, hypovolaemic and cardiogenic shock, and if untreated, death. It has been estimated that the disease afflicts approximately 60,000 dogs in the USA each year with a mortality rate ranging from 7 to 60 per cent depending on accessibility to adequate veterinary care. The cause is unknown. While diet was at one time believed to be associated with the genesis of the disease, critical review of available data provides no evidence to support this hypothesis. A variety of predisposing or risk factors have been identified but none is suspected of being the cause, indeed, the disorder may have a multiple aetiology. Current thinking suggests that the final common pathway in the development of GDV may be an inhibition of gastric motility and emptying. This could come about through a primary disruption of normal gastric electrical patterns or through the effect of extraneous stressful events that disrupt gastric motility. After dilatation a series of potentially lethal events is unleashed which include compression of the caudal vena cava, pooling of blood in the microcirculation of the viscera and hindlimbs, metabolic acidosis, gastric necrosis, cardiac arrhythmias, disseminated intravascular coagulation, hypotensive and cardiogenic shock and death. Nevertheless, even advanced cases can survive if treated appropriately. If the cause could be identified logical prophylaxis might follow. Studies at the University of Florida have failed to demonstrate any effect of diet on gastric function in large breed dogs, suggesting that diet is probably not the cause of the disease. Researchers at Colorado State University also found no association with diet in clinical patients. Recent studies at the University of Florida have revealed distinct abnormalities in gastric electrical activity in GDV patients. In human patients these abnormalities, called dysrhythmias, have been associated with gastric distention, bloating, delayed emptying, nausea and retching. Unfortunately, dysrhythmias are also present, albeit to a lesser degree, in experimental GDV. These findings leave unanswered the question as to whether abnormalities in gastric motility play a role in the genesis of GDV.     

Use of breed-specific ranges for the vertebral heart scale as an aid to the radiographic diagnosis of cardiac disease in dogs.

The vertebral heart scale was measured on right lateral recumbent thoracic radiographs of 320 dogs of six popular breeds, including for each breed at least 20 dogs with no clinical signs of cardiovascular or respiratory disease and at least 19 dogs with cardiac or respiratory disease. There were significant differences between the mean values of the scale for the different breeds; the normal boxer dogs had a significantly higher mean value than the normal dogs of all the other breeds, and the labrador retrievers had a significantly higher mean value than all the other breeds except the boxer and the cavalier King Charles spaniel. For all the breeds except the boxer, there was a trend for dogs with cardiac disease (but not respiratory disease) to have higher mean values on the scale than normal dogs of the same breed; however, at the optimal value of the scale for distinguishing between dogs of each breed with and without cardiac disease, the sensitivity and specificity were relatively low, in the range 58 to 83 per cent. The scale was most accurate for the diagnosis of cardiac disease in the Yorkshire terrier and the cavalier King Charles spaniel, breeds affected by predominantly dilative forms of cardiac disease. In contrast, it was very inaccurate in the boxer, a breed that has a higher incidence of cardiac diseases associated with concentric hypertrophy.     

Benefits of prophylactic gastropexy for dogs at risk of gastric dilatation-volvulus

The lifetime probability of death from gastric dilation–volvulus (GDV) for five dog breeds was estimated based on published breed-specific longevity and GDV incidence. These breeds were Great Dane, Irish Setter, Rottweiler, Standard Poodle and Weimaraner. Lifetime risk (95% CI) of GDV in these breeds ranged from 3.9% (0–11.2%) for Rottweiler to 36.7% (25.2–44.6%) for Great Dane.

A decision-tree analysis for prophylactic gastropexy—using lifetime probability of death from GDV and expected cost savings for veterinary services as outcome measures—was undertaken to determine the preferred course of action in several dog breeds. Prophylactic gastropexy was the preferred choice of action for all breeds examined, with the reduction in mortality (versus no gastropexy) ranging from 2.2-fold (Rottweiler) to 29.6-fold (Great Dane). Assuming a prophylactic gastropexy costs US$ 400, the procedure was cost-effective when the lifetime risk of GDV was ≥34%. The maximum and minimum estimated breakeven costs for the gastopexy procedure ranged from US$ 20 (Rottweiler) to US$ 435 (Great Dane). The cost-effectiveness of prophylactic gastropexy was most sensitive to the cost of treating GDV (US$ 1500). Prophylactic gastropexy raises ethical issues that need to be considered by veterinarians and dog breeders.     

ULTRASONOGRAPHIC EVALUATION OF ADRENAL GLAND SIZE COMPARED TO BODY WEIGHT IN NORMAL DOGS

The accepted cut‐off value for adrenal gland maximum diameter of 0.74 cm to distinguish adrenal gland enlargement in dogs regardless of body weight may not be appropriate for small to medium breed dogs. The purpose of the current retrospective study was to examine adrenal gland dimensions as a function of body weight in healthy dogs in three weight categories (< 10 kg, 10–30 kg, and > 30 kg) representing small, medium, and large breeds, respectively, to establish greater confidence in determining if adrenal gland size is abnormal. The measurements of length (sagittal plane), cranial and caudal pole thickness (sagittal and transverse planes), and caudal pole width (transverse plane) of both adrenal glands were obtained ultrasonographically in clinically healthy dogs (n = 45) with 15 dogs in each weight group. Findings support our hypothesis that adrenal gland size correlates with body weight in normal dogs, and more precise reference intervals should be created for adrenal gland size by categorizing dogs as small, medium, or large breed. The caudal pole thickness of either adrenal gland in a sagittal plane was the best dimension for evaluating adrenal gland size based on low variability, ease, and reliability in measurement.     

Gastric dilatation-volvulus in dogs

Gastric dilatation-volvulus (GDV) is a disease in which there is gross distension of the stomach with fluid or gas and gastric malpositioning. It causes pathology of multiple organ systems and is rapidly fatal. It is common in large- and giant-breed dogs. The disease appears to have a familial predisposition. Thoracic depth/width ratio also appears to predispose dogs to GDV. Implicated dietary factors include dietary particle size, frequency of feeding, speed of eating, aerophagia and an elevated feed bowl. A fearful temperament and stressful events may also predispose dogs to GDV. Abdominal distension, non-productive retching, restlessness, signs of shock, tachypnoea and dyspnoea are possible clinical signs. Initial treatment includes treatment of shock and gastric decompression. Surgical treatment should be performed promptly. There are no studies comparing the use of different anaesthetic agents in the anaesthetic management of GDV. Pre-medication with an opioid/benzodiazepine combination has been recommended. Induction agents that cause minimal cardiovascular changes such as opioids, neuroactive steroidal agents and etomidate are recommended. Anaesthesia should be maintained with an inhalational agent. Surgical therapy involves decompression, correction of gastric malpositioning, debridement of necrotic tissue, and gastropexy. Options for gastropexy include incisional, tube, circumcostal, belt-loop, incorporating, and laparoscopic gastropexy. Expected mortality with surgical therapy is 15-24%. Prognostic factors include mental status on presentation, presence of gastric necrosis, presence of cardiac arrhythmia and plasma lactate levels. Prophylactic gastropexy should be considered in dogs identified as being at high risk.     

Mortality in north american dogs from 1984 to 2004: an investigation into age-, size-, and breed-related causes of death

Background: Anecdotal beliefs and limited research suggest variable patterns of mortality in age, size, and breed cohorts of dogs. Detailed knowledge of mortality patterns would facilitate development of tailored health‐maintenance practices and contribute to the understanding of the genetic basis of disease. Hypothesis/Objectives: To describe breed‐specific causes of death in all instances of canine mortality recorded in the Veterinary Medical Database (VMDB) 1 between 1984 and 2004. We hypothesized that causes of death, categorized by organ system (OS) or pathophysiologic process (PP), would segregate by age, body mass, and breed. Animals: 74,556 dogs from the VMDB for which death was the outcome of the recorded hospital visit. Methods: Retrospective study. Causes of death from abstracted VMDB medical records were categorized by OS and PP and analyzed by age, breed, and breed‐standard mass of dog. Results: Causes of death, categorized by OS or PP, segregated by age, breed, and breed‐standard mass. Young dogs died more commonly of gastrointestinal and infectious causes whereas older dogs died of neurologic and neoplastic causes. Increasing age was associated with an increasing risk of death because of cardiovascular, endocrine, and urogenital causes, but not because of hematopoietic or musculoskeletal causes. Dogs of larger breeds died more commonly of musculoskeletal and gastrointestinal causes whereas dogs of smaller breeds died more commonly of endocrine causes. Conclusions and Clinical Importance: Not all causes of death contribute equally to mortality within age, size, or breed cohorts. Documented patterns now provide multiple targets for clinical research and intervention.