Canine keratoconjunctivitis sicca: disease trends in a review of 229 cases

OBJECTIVES: To investigate the disease patterns in dogs with keratoconjunctivitis sicca referred to the University of Glasgow Small Animal Hospital. METHODS: A retrospective study of 229 cases was carried out. RESULTS: There were 44 breeds in the study, with four breeds, English cocker spaniels, cavalier King Charles spaniels, West Highland white terriers and shih-tzus, making up 58 per cent of the cases. Among these four breeds, two breed-dependent disease patterns, one chronic and one acute, were identified. English cocker spaniels and West Highland white terriers had a mean age at onset of clinical signs of five years and one month and five years and six months, respectively, with more females affected than males. Clinical signs consisted predominantly of conjunctival hyperaemia and mucopurulent discharge, with a relatively low incidence of ulcerative keratitis. In contrast, cavalier King Charles spaniels and shih-tzus showed a more acute disease pattern with a biphasic age distribution at 0 to less than two years of age, and four to less than six and six to less than eight years of age, respectively, with more males affected than females and a significantly higher incidence of ulcerative keratitis in some cases resulting in corneal perforation. CLINICAL SIGNIFICANCE: The study reveals interbreed differences with respect to sex, age and risk of ulcerative keratitis which have not been detailed previously in a referral population.     

Plasma amino acid concentrations in 36 dogs with histologically confirmed superficial necrolytic dermatitis

Plasma amino acid concentrations were measured in 36 dogs diagnosed with superficial necrolytic dermatitis (SND) via skin biopsy. The median age of the dogs was 10 years, and 27 out of 36 (75%) were male. Twenty-two out of 36 (61%) of the dogs were accounted for by six breeds; West Highland white terriers (six), Shetland sheepdogs (five), cocker spaniels (four), Scottish terriers (three), Lhasa apsos (two) and Border collies (two). The mean concentration (+/- standard deviation) was calculated for each measured plasma amino acid and compared to previously documented concentrations of plasma amino acids measured in dogs with acute and chronic hepatitis. The ratio of branched chain amino acids to aromatic amino acids in the dogs with SND was 2.6, slightly lower than that in normal dogs. The mean plasma amino acid concentrations for dogs with SND were significantly lower than for dogs with acute and chronic hepatitis. A metabolic hepatopathy in which there is increased hepatic catabolism of amino acids is hypothesized to explain the hypoaminoacidaemia seen in SND.     

Breed, age and gender distribution of dogs with chronic hepatitis in the United Kingdom

Standardised histological criteria are now available for the diagnosis of canine chronic hepatitis (CH). CH is common in dogs, but no studies have reported breed, age and gender distributions in the United Kingdom (UK). The objective of this study was to determine which breeds had an increased risk for developing CH in the UK and to report the age and gender distribution for those breeds. The databases of six veterinary histopathology laboratories were searched for cases with a histological diagnosis of CH according to standardised criteria. The breed, age and gender of dogs was recorded and compared to a control population to calculate the odds ratio and 95% confidence intervals for developing CH. A total of 551 cases of CH were identified, consisting of 61 breeds. Nineteen breeds were represented by five or more cases. Breeds with an increased risk for developing CH included the American cocker spaniel, Cairn terrier, Dalmatian, Dobermann pinscher, English cocker spaniel, English springer spaniel, Great Dane, Labrador retriever and Samoyed. The median age at diagnosis for all breeds with CH was 8 years (range 7 months to 16 years). Dalmatians, Dobermann pinschers and English springer spaniels with CH were significantly younger than Cairn terriers, English cocker spaniels and Labrador retrievers with CH. Females were over-represented when all cases were examined together. In conclusion, several breeds in the UK have an increased risk of CH, some of which have not been previously reported.     

Differences between breeds of dog in a measure of heart rate variability

The vasovagal tonus index (VVTI), a time-domain indicator of heart rate variability, was measured in 92 dogs of six breeds (German shepherd dogs, labrador retrievers, cocker spaniels, boxers, bulldogs and cavalier King Charles spaniels). There was a significant difference in VVTI between the six breeds (P = 0.003). Brachycephalic dogs had a higher VVTI than other types of dog (P < 0.005), and when comparing individual breeds brachycephalic breeds tended to have a higher VVTI than non-brachycephalic breeds, although the difference was not always significant. The VVTI was negatively correlated with heart rate (P < 0.01) and dogs suffering from congestive heart failure had a lower VVTI than other dogs, whether compared within or between breeds (P < 0.01).     

Prevalence and features of canine atopic dermatitis in Hungary

Medical records of 600 dogs diagnosed with atopic dermatitis were reviewed and evaluated with reference to history, geographical distribution, breed predilection, clinical signs and positive reactions to allergens as determined by intradermal skin testing (IDT) manufactured by Artuvetrin Laboratories. In 66.6% of dogs, the age of onset of atopic dermatitis was between 4 months and 3 years. Dogs living in the garden suburb of Budapest were more sensitive to house dust mites, fleas and moulds, and dogs from the western part of Hungary were more sensitive to weeds than to other allergens (p < 0.01). Positive reactions were most common to Dermatophagoides farinae followed by human dander. The breed distribution found in the present study was consistent with that reported in the literature, except for the breeds Hungarian Vizsla, Pumi, French bulldog, Doberman Pinscher and Bobtail which were over-represented among atopic dogs compared to the breed distribution of the general dog population of a large city in Hungary. Breeds with verified adverse reaction to food were Cocker spaniels, French bulldogs, Bullmastiffs, Bull terriers, St. Bernards, Tervurens, West Highland White terriers and American Staffordshire terriers (p < 0.05). The clinical signs of atopic dermatitis and their occurrence are in accordance with the data described in the literature.     

Hereditary copper toxicosis in West Highland white terriers

Histologic, histochemical and atomic absorption studies on liver tissue from 71 West Highland white terriers are reported. Twenty-seven dogs had histologically normal liver and copper concentration comparable to mongrel control dogs. Forty-four dogs had hepatic copper concentrations up to 22 times the mean copper concentration found in clinically normal mongrel dogs. Hepatitis, hepatic necrosis and cirrhosis were associated with the increased copper concentration in some dogs. Matings between dogs with high liver copper concentration produced pups with high liver concentration. The copper storage defect is inherited.     

Factors associated with elevated cutaneous Malassezia p a chyderm a tis populations in dogs with Pruritic skin isease

The prevalences of breeds and concurrent diseases in a group of 40 dogs with pruritic skin disease associated with elevated cutaneous Malassezia pachydermatis populations were compared with samples of a dermatological hospital population. The ages and genders of the affected dogs were comparable to those of the dermatology population. Basset hounds, cocker spaniels and West Highland white terriers were significantly overrepresented. Concurrent diseases were diagnosed in 27 dogs, of which 15 were atopic. However, the prevalences of atopic disease, primary keratinisation defects and endocrinopathies in dogs with elevated cutaneous M pachydermatis populations were comparable to those in the dermatology population as a whole. These results indicate that certain breeds are predisposed to the development of elevated cutaneous M pachydermatis populations and that concurrent skin diseases can frequently be identified in affected dogs. However, the relationship between these concurrent diseases and abnormal M pachydermatis populations remains unclear.     

Variation in position of the medial fabella in West Highland white terriers and other dogs

O bjectives : To investigate whether West Highland white terriers exhibit significant variation in the position of the medial fabella compared to both small and large breed dogs.
M ethods : Criteria for the normal location of the medial fabella on a caudocranial radiograph were established. A retrospective analysis was undertaken of a consecutive series of bilateral caudocranial stifle joint radiographs from 70 West Highland white terriers, 100 small and 100 large control dogs by three reviewers. Medial fabellar location, cruciate ligament disease and medial patellar luxation were examined within and between groups.
R esults : Abnormal medial fabellar location was identified in 70 per cent, 9 per cent and 0 per cent of West Highland white terriers, small dogs and large dogs, respectively. In the vast majority of the affected dogs, the fabella was found in a mediodistal location. Presence of concurrent cranial cruciate ligament disease or medial patellar luxation and body weight was excluded as confounding factors.
C linical S ignificance : West Highland white terriers appear predisposed to, and have a high prevalence of, an abnormal mediodistal location of the medial fabella. The authors suggest this is an incidental finding and should not be confused with true pathological fabellar displacement.     

Incidence of and risk factors for atopic dermatitis in a Swedish population of insured dogs

The incidence of atopic dermatitis was estimated to be 1.7 cases per 1000 dog-years at risk in a population of insured Swedish dogs whose insurance claims for the period 1995 to 2002 were examined. Several factors were found to increase the risk of having a recorded claim, including living in a city or in central or southern Sweden, being born in the autumn, and belonging to a high-risk breed. Bull terriers had the highest risk, with 21 cases per 1000 dog-years at risk, and several other breeds including boxers and West Highland white terriers also had an above average risk. There was no difference in the incidence between the sexes. There was a slight increase in the incidence during the period. In a subset of the data that consisted only of dogs from 15 high-risk breeds, the overall survival appeared to be lower for the dogs that had had an insurance claim for the disease.     

Effects of whelping and season of the year on the interoestrous intervals in dogs

An analysis of 319 interoestrous intervals of 36 beagles, 36 German shepherd dogs and 20 labrador retrievers was made to study the influence of whelping on the length of this interval and the within-year variation in length of interoestrous intervals and timing of the oestrous periods. The mean interoestrous interval was significantly longer for beagles (247±5 days) than for German shepherd dogs and labrador retrievers (both 198±5 days)(P<0–001). For bitches that had not whelped there were no significant differences between breeds (beagles 172+10; German shepherd dogs 166±6; and labrador retrievers 172±7 days). The mean interoestrous interval after whelping was significantly lengthened in all breeds (P<0–001). This increase was more pronounced for beagles (84 days)(P<0–001) than for German shepherd dogs (58 days) and labrador retrievers (52 days). Heat periods were evenly distributed over the year for the labrador retrievers and German shepherd dogs that were kept as family pets. For the beagles kept as a colony and housed outdoors without heating or supplementary light, there were significant differences between months (P<0001), with a peak in May. The longest interoestrous intervals were found in beagle bitches that had been in oestrous and whelped during autumn.     

A perspective on copper and liver disease in the dog.

Copper is a ubiquitous trace metal necessary for normal function of a variety of cellular proteins. Intracellular copper metabolism is complex, and only a few of the proteins/genes involved are known. Copper deficiency does not appear to be a clinical problem in dogs. Excess copper accumulation in the liver as a cause of hepatitis and cirrhosis was first demonstrated among Bedlington terriers. Subsequently, copper accumulation in the liver has been shown to occur in several other breeds of dogs. Excess hepatic copper has been found in dogs with normal liver histology, dogs with hepatitis, and dogs with end stage cirrhosis. Evidence is accumulating that copper is a cause of liver disease in breeds of dogs other than Bedlington terriers. Moreover, as more data are accumulated, the copper storage disease appears to have characteristics that are very similar among all of the affected breeds.     

COMPARISON BETWEEN SEDATION AND GENERAL ANESTHESIA FOR HIGH RESOLUTION COMPUTED TOMOGRAPHIC CHARACTERIZATION OF CANINE IDIOPATHIC PULMONARY FIBROSIS IN WEST HIGHLAND WHITE TERRIERS

Canine idiopathic pulmonary fibrosis is a progressive interstitial lung disease mainly affecting West Highland white terriers. Thoracic high‐resolution computed tomographic (T‐HRCT) findings for Canine idiopathic pulmonary fibrosis acquired under general anesthesia have been described previously. However, the use of general anesthesia may be contraindicated for some affected dogs. Sedation may allow improved speed and safety, but it is unknown whether sedation would yield similar results in identification and grading of Canine idiopathic pulmonary fibrosis lesions. The aim of this prospective, observational, method‐comparison, case‐control study was to compare findings from T‐HRCT images acquired under sedation versus general anesthesia for West Highland white terriers affected with Canine idiopathic pulmonary fibrosis (n = 11) and age‐matched controls (n = 9), using the glossary of terms of the Fleischner Society and a scoring system. Ground‐glass opacity was identified in all affected West Highland white terriers for both sedation and general anesthesia acquisitions, although the Ground‐glass opacity extent varied significantly between the two acquisitions (P < 0.001). Ground‐glass opacity was the sole lesion observed in control dogs (n = 6), but was less extensive compared with affected West Highland white terriers. Identification and grading of a mosaic attenuation pattern differed significantly between acquisitions (P < 0.001). Identification of lesions such as consolidations, nodules, parenchymal and subpleural bands, bronchial wall thickening, and bronchiectasis did not differ between acquisitions. The present study demonstrated that T‐HRCT obtained under sedation may provide different information than T‐HRCT obtained under general anesthesia for identification and grading of some Canine idiopathic pulmonary fibrosis lesions, but not all of them. These differences should be taken into consideration when general anesthesia is contraindicated and sedation is necessary for evaluating West Highland white terriers with Canine idiopathic pulmonary fibrosis.     

Use of 64Copper Measurements to Diagnose Canine Copper Toxicosis

Inherited canine copper toxicosis is a serious problem in Bedlington terriers and West Highland White terriers, and may also be a problem in other less-studied breeds. Affected dogs become ill at midlife with progressive and ultimately fatal liver disease. Treatments for removal of copper and prevention of copper accumulation are available, but are most effective if begun before the dog becomes ill. Until recently diagnosis has not been available until the dog is 1 year of age, and then only by an invasive liver biopsy with determination of liver copper concentration. The authors studied the use of 64copper for early diagnosis of canine copper toxicosis. Two procedures were evaluated. The first involved measuring the concentration of 64copper in blood 24 hours after oral administration of the radioisotope. At this time, 64copper was associated primarily with ceruloplasmin secreted into the blood by the liver. This procedure is useful in the diagnosis of the human counterpart, Wilson's disease. However, the authors found it to be nondiscriminatory between affected and unaffected dogs. In contrast, the second procedure, which involved measuring 64copper excreted in stool during 48 hours after an intravenous dose of radioisotope, yielded results that differentiated most affected and unaffected dogs.     

Characteristics of 234 dog bite incidents in Ireland during 2004 and 2005

Information was obtained by telephone interview from 100 dog owners whose dog had bitten a person, and from 134 victims of bites by a dog not owned by the victim. Three-quarters of the victims were female and aged from 21 to 60 years. The majority of the dogs were owned, male, two to six years old, over 10 kg in bodyweight and belonged to the popular breeds: collies, cocker/springer spaniels, terrier breeds, Jack Russell terriers, German shepherd dogs, golden retrievers and crossbreeds. The numbers of bites by the different breeds indicated that those that inflicted the most bites were the popular breeds rather than the breeds with any greater propensity to bite. Most attacks were rapid single bites and in 50 per cent of the cases, neither the owner nor the victim was able to identify any signal of the dog's intention to bite. Overall, 21 per cent of the incidents were rated as 'serious' and 2 per cent as 'life threatening'. One fifth of the dogs were euthanased as a result of the incident. Half the incidents required professional medical assistance for the victim. Almost half the incidents took place while the victim was walking or passing close to the dog's territory, or while the victim was interacting with the dog at home.     

Presence and impact of the exercise-induced collapse associated DNM1 mutation in Labrador retrievers and other breeds

The impact of the mutation causing dynamin 1 (DNM1)-associated exercise-induced collapse (d-EIC) was determined in a retrospective genetic survey. The frequency of DNM1 mutant allele carriers in Labrador retrievers from conformation show, field trial/hunt test, pet or service lines ranged from 17.9% to 38.0% and the frequency of homozygous mutant (EE genotype) individuals ranged from 1.8% to 13.6%; 83.6% of these EE Labradors were reported to have collapsed by 4 years of age. DNM1 mutation carriers and EE dogs with a collapse phenotype were also detected in Chesapeake Bay retrievers, Curly-coated retrievers, Boykin spaniels, Pembroke Welsh corgis and mixed breed dogs thought to be Labrador retriever crosses. The DNM1 mutation was not identified in Golden, Flat-coated, or Nova Scotia duck tolling retrievers, or 15 other non-retrieving breeds. Veterinarians and breeders should be aware that the DNM1 EE genotype is not completely penetrant and that d-EIC is a widespread health concern in several very popular breeds, as well as breeds whose genetic similarity to retrievers is not obvious.     

Risk factors for medial meniscal injury in association with cranial cruciate ligament rupture

Objectives : To determine the significant risk factors for medial meniscal injury in naturally occurring cranial cruciate ligament rupture and to quantify the risk using multivariate analysis. Methods : A retrospective case control study was performed of dogs that had undergone surgery for cranial cruciate ligament rupture. Data recorded included patient signalment (age, breed and sex), the duration of the lameness, the extent of the cranial cruciate ligament rupture (complete or partial) and the condition of the medial meniscus. Logistic regression was used to analyse the relationship between these variables and tears in the medial meniscus. Results : One hundred and sixty-one of 443 stifles (36·3%) in 366 dogs had a medial meniscal tear. The risk of a medial meniscal tear was increased by 12·9 times in association with complete cranial cruciate ligament rupture (OR 12·9; 95% CI 6·8 to 24·2), by approximately 2·6% for each additional week of lameness (OR 1·026; 95% CI 1·009 to 1·043) and by approximately 1·4% for each additional kilogram of bodyweight (OR 1·014; 95% CI 1·000 to 1·028). Golden retrievers and Rottweilers were at increased risk and West Highland white terriers were at reduced risk of medial meniscal tears compared with Labrador retrievers. Clinical Significance : To minimise the risk of medial meniscal tears, surgical stabilisation should not be unnecessarily delayed.     

Study of 253 dogs in the United Kingdom with diabetes mellitus

Clinical information and blood samples were collected from 253 dogs with naturally occurring diabetes mellitus. Over half of them were labrador retrievers, collies, Yorkshire terriers or crossbred dogs, and approximately 80 per cent of them were diagnosed between the ages of five and 12 years. The majority of the dogs were receiving insulin therapy once a day, but in the dogs receiving insulin injections twice a day there was a trend for lower serum fructosamine concentrations, suggesting better glycaemic control. The proportion of female dogs with diabetes was lower than in previous surveys. The disease was diagnosed more commonly in the winter months, a seasonal pattern also observed in human beings with diabetes, suggesting that similar environmental factors might be involved in the disease.     

Hepatitis and copper accumulation in Skye terriers

Livers of nine related Skye terriers with liver disease were evaluated for histological changes and copper content. Lesions ranged from hepatocellular degeneration and necrosis (zone 3) with intracanalicular cholestasis and mild inflammation, to chronic hepatitis with cholangioplasia and cirrhosis. Excess copper (801-2,257 micrograms/g) was related to the severity of cholestasis. Skye terrier hepatitis is a distinct disease entity and may be derived from a disorder of intracellular bile metabolism culminating in disturbed bile secretion and the accumulation of copper.     

Ultrasonographic Adrenal Gland Measurements in Healthy Yorkshire Terriers and Labrador Retrievers

An upper threshold of 7.4 mm for maximal adrenal gland diameter is commonly used to detect pituitary‐dependent hyperadrenocorticism ultrasonographically in dogs. There is a substantial overlap between adrenal gland diameter of healthy dogs and of those with pituitary‐dependent hyperadrenocorticism. The aim of this study is to determine the measurements of both adrenal glands, in particular, of the height at the caudal glandular pole in a longitudinal plane, in the Labrador retriever and Yorkshire terrier, two breeds widely represented in the population suspected of hyperadrenocorticism. Seventeen Labrador retrievers and 24 Yorkshire terriers considered healthy were included in the study. Adrenal gland measurements were taken on static images and comprised in measurements of the length in a longitudinal plane (L), of the height at the cranial (CrHLG) and caudal pole (CdHLG) in a longitudinal plane and in a transverse plane (CrHTR and CdHTR, respectively), and of the width at the cranial and caudal poles in a transverse plane (CrWTR and CdWTR, respectively). This study established new upper thresholds for the left and right height at the caudal pole measured in a longitudinal plane: 7.9 mm (left) and 9.5 mm (right) for the Labrador retrievers and 5.4 mm (left) and 6.7 mm (right) for the Yorkshire terriers. All the measurements were significantly different between the two breeds. There was a significant relationship between CdHTR and CdHLG, and the age of the dogs for both breeds.