Estimation of heritability for hip dysplasia in German Shepherd Dogs in Finland

The heritability of hip dysplasia in the German Shepherd Dog was estimated by applying the animal model and the Restricted Maximum Likelihood (REML) method to a data-set which consisted of the hip scores of 10 335 dogs. Fixed effects of the model were the month and the year of birth, screening age, the panelist responsible for screening and the origin of the animal's sire. The litter and the breeder had only minor effects on hip joints. Heritability estimates were moderate (0.31–0.35). The moderate heritability, which was found in this study, enables a much better genetic gain in the breeding programme, if proper evaluation methods, such as BLUP animal model, and effective selection is used instead of phenotypic selection.     

Canine hip dysplasia: study of heritability in 401 litters of German Shepherd dogs

Heritability of hip dysplasia was estimated to be about 0.4 to 0.5 when based on the radiographic evaluations of the hip joints of 2,404 German Shepherd Dogs born at The Armed Forces Dog Training Center in Sweden. The material included all dogs in 401 litters born at the Center from 1965 through 1973 that reached the age of 15 months. To be expected with such high heritability, frequency of hip dysplasia in the offspring was shown to be affected by the hip joint status of sire and dam as well as by the hip joint status of their parents and littermates. Even matings between sires with normal hip joints and dams with only slight dysplasia resulted in significantly higher frequency of hip dysplasia in the offspring, when compared with the frequency if both sires and dams had normal hip joints. Frequency of hip dysplasia in the progeny of sires with normal hip joints varied greatly. Since 1973, selection of the breeding stock has been based on hip joint status (phenotype) of the breeding animals and of their relatives as well as on what had become known about frequency of hip dysplasia in the litters already born (progeny testing). In this way, frequency of hip dysplasia in 347 dogs born at the Center during 1975 was lowered to 28%. This figure should be compared with the figure of 50%, which represents the frequency of hip dysplasia in the kennel up to 1970, when selection was not as strict as could be expected in a well-controlled kennel.     

Pituitary dwarfism in German Shepherd Dogs

Eleven German Shepherd dogs with pituitary dwarfism were examined. They were severely stunted in growth and possessed abnormal hair coats with persistence of the soft puppy (lanugo) coat and symmetrical areas of alopecia. Various other physical defects were often present in affected dogs. Detailed hormonal studies demonstrated a severe deficiency in growth hormone in all five cases so evaluated. A decrease in somatomedin activity was present in three of these cases. Changes in growth plates epiphyses and ossification centres were apparent on radiographic examination of four of the eleven dogs. Epiphyseal dysgenesis was confirmed histologically in two of these cases. Of the six brains which were examined post mortem, four showed large cystic lesions involving the adenohypo–physis and two had pituitary hypoplasia with virtual absence of adenohy–pophyseal tissue.     

Symmetry of hip dysplasia traits in the German Shepherd Dog in Australia

Canine hip dysplasia (CHD) is a common and debilitating developmental condition of the canine coxofemoral (hip) joint, exhibiting a multifactorial pattern of inheritance. British Veterinary Association hip traits (BVAHTs) are nine radiographic features of hips used in several countries to ordinally score both the right and left hip of potential breeding candidates to assess their suitability for breeding. The objective of this study was to examine some aspects of the relationship between contralateral scores for each BVAHT in a cohort of 13 124 Australian‐registered German Shepherd Dogs. Goodman and Kruskal gamma coefficients of 0.48–0.95 and correlation coefficients of 0.50–0.74 demonstrate that the association between right and left hip scores varies between moderate and strong for BVAHTs. Principal component analysis of scores detected a sizeable left‐versus‐right effect, a finding supported by symmetry and quasi‐symmetry analyses which found that seven of the nine BVAHTs display significant marginal asymmetry. Dogs showing asymmetry for one BVAHT are significantly more likely to display asymmetry at other BVAHTs. When asymmetry is expressed as a binary trait (either symmetrical or asymmetrical), it displays low to moderate heritability. Estimates of genetic correlations between right and left scores are very high for all BVAHTs (>0.945), suggesting right and left scores for each BVAHT are largely determined by the same set of genes. The marginal asymmetries are therefore more likely to be of environmental and non‐additive genetic origin. In breeding programmes for CHD, we recommend that scores from both hips be used to estimate breeding values, with a term for side‐of‐hip included in the model to account for score variation owing to asymmetry.     

Sacral osteochondrosis in two German Shepherd Dogs

Two young adult male castrated German Shepherd Dogs were referred for evaluation of intermittent episodes of hindlimb pain. Physical examination suggested lumbosacral stenosis, and plain radiographs and computed tomography revealed lesions consistent with sacral osteochondrosis. One dog had osteochondral fragments removed surgically; the other was managed conservatively. The surgically treated dog had complete resolution of clinical signs whereas the dog managed conservatively had repeated episodes of mild pain and received one short course of non-steroidal anti-inflammatory medication in 18 months. Sacral osteochondrosis has not been previously reported in Australia.     

Heritability of Exocrine Pancreatic Insufficiency in German Shepherd Dogs

Background: Several studies have revealed that exocrine pancreatic insufficiency (EPI) is an inherited disease in German Shepherd Dogs (GSDs). Pedigree analyses have suggested an autosomal recessive inheritance model. Objective: Test mating of 2 dogs with EPI. Animals: A sire and dam purebred GSD both with EPI and a litter of 6 puppies. Methods: Test mating and long‐term follow‐up of offspring. The pancreas was biopsied via laparotomy on 26 occasions. Serum trypsin‐like immunoreactivity was measured. Study was approved by Animal Ethics Committee. Results: During the 12‐year study period only 2 of the 6 offsprings developed pancreatic acinar atrophy (PAA). In 1 puppy, end‐stage PAA and in the other puppy partial PAA was diagnosed. Conclusions and Clinical Importance: PAA is not a congenital disease in GSDs. This study provided evidence that PAA is not inherited in a simple autosomal recessive fashion.     

Inheritance of pancreatic acinar atrophy in German Shepherd Dogs

OBJECTIVE: To assess the heritability of pancreatic acinar atrophy (PAA) in German Shepherd Dogs (GSDs) in the United States. ANIMALS: 135 GSDs belonging to 2 multigenerational pedigrees. PROCEDURE: Two multigenerational pedigrees of GSDs with family members with PAA were identified. The clinical history of each GSD enrolled in the study was recorded, and serum samples for canine trypsin-like immunoreactivity (cTLI) analysis were collected from 102 dogs. Dogs with a serum cTLI concentration < or = 2.0 microg/L were considered to have exocrine pancreatic insufficiency (EPI) and were assumed to have PAA. RESULTS: Pedigree I consisted of 59 dogs and pedigree II of 76 dogs. Serum cTLI concentrations were measured in 48 dogs from pedigree I and 54 dogs from pedigree II. A total of 19 dogs (14.1%) were determined to have EPI, 9 in pedigree I (15.3%) and 10 in pedigree II (13.6%). Of the 19 dogs with EPI, 8 were male and 11 were female. CONCLUSIONS AND CLINICAL RELEVANCE: Evaluation of data by complex segregation analysis is strongly suggestive of an autosomal recessive mode of inheritance for EPI in GSDs in the United States.     

Evaluation of risk factors for degenerative joint disease associated with hip dysplasia in German Shepherd Dogs, Golden Retrievers, Labrador Retrievers, and Rottweilers.

OBJECTIVE: To determine whether age, breed, sex, weight, or distraction index (DI) was associated with the risk that dogs of 4 common breeds (German Shepherd Dog, Golden Retriever, Labrador Retriever, Rottweiler) would have radiographic evidence of degenerative joint disease (DJD) associated with hip dysplasia. DESIGN: Cross-sectional prevalence study. ANIMALS: 15,742 dogs. PROCEDURE: Hips of dogs were evaluated radiographically by use of the ventrodorsal hip-extended view, the compression v ew, and the distraction view. The ventrodorsal hip-extended view was examined to determine whether dogs had DJD. For each breed, a multiple logistic regression model incorporating age, sex, weight, and DI was created. For each breed, disease-susceptibility curves were produced, using all dogs, regardless of age, and dogs grouped on the basis of age. RESULTS: Weight and DI were significant risk factors for DJD in all breeds. For German Shepherd Dogs, the risk of having DJD was 4.95 times the risk for dogs of the other 3 breeds combined. In all breeds, the probability of having DJD increased with age. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that the probability of having hip DJD increased with hip joint laxity as measured by use of DI. This association was breed-specific, indicating that breed-specific information on disease susceptibility should be incorporated when making breeding decisions and when deciding on possible surgical treatment of hip dysplasia.     

Genetic Analysis of Ventricular Arrhythmia in Young German Shepherd Dogs

Background: Ventricular arrhythmias (VA) and sudden death are inherited in German Shepherd Dogs (GSDs).
Objectives: To estimate the genetic parameters (heritabilities and correlations) of 3 traits of VA (single premature ventricular complexes (PVCs), 2 consecutive PVCs (couplets), and 3 or more consecutive PVCs—ventricular tachycardia [VT]).
Animals: Three hundred and ninety-eight GSDs.
Methods: Prospective, observational, case control study. Dogs were phenotyped by 24-hour ambulatory ECG from 6 to 45 weeks of age. Edited ECG records included the number of incidents of (1) single PVCs, (2) couplets, and (3) VT.
Results: A data set of 1,239 Holter records from 398 GSDs was used to estimate genetic variables. Phenotypic correlations for affectedness (binarily coded 0/1) of the 3 traits ranged from 0.55 to 0.74, whereas correlations for severity (continuous values of 24-hour VA counts) ranged from 0.26 to 0.39. Estimates of genetic correlation among the severity traits were 0.06 to 0.27. Estimated heritabilities were 0.54, 0.54, and 0.46 for affectedness and 0.33, 0.69, and 0.69 for severity of PVCs, couplets, and VT, respectively. Month and year of birth and age at ECG recording had significant effects on all 3 traits. Season of ECG recording had a significant effect on the number of single PVCs, but not couplets or incidents of VT. Age of onset differed, with single PVCs appearing an average of 4 days earlier than couplets and VT.
Conclusion: These results imply a strong genetic component for this disease but suggest that differences in the 3 traits should be taken into consideration in studies to identify the underlying genes.     

Influence of femoral head and neck conformation on hip dysplasia in the German Shepherd dog.

We investigated the prevalence of an anatomic variant of the proximal femur, termed the broomstick-like femoral head and neck formation, and its influence on the Féderation Cynologique Internationale (FCI) hip dysplasia score in 294 German Shepherd dogs. One-hundred and eighty (61%) of the 294 dogs in our study had this anatomic variant. The calculated area of the femoral heads in dogs with a broomstick-like conformation was 4.5 +/- 0.6 cm2 on the hip-extended view. In dogs with a normal femoral head, the calculated area of the femoral head was significantly larger at 4.8 +/- 0.6 cm2 (P < 0.05). In the frog-leg view, there was no significant difference in femoral head area between dogs with the broomstick-like conformation and normal dogs. There was no difference in the antetorsion angle between dogs with broomstick-like conformation and normal dogs. There was also no difference in the distraction ratio between the two phenotypes. The official FCI hip score was similar in dogs with and without the broomstick-like conformation. The average heritability of the broomstick-like conformation was 0.3 +/- 0.1, suggesting heritable influence. We conclude that the broomstick-like conformation is a common finding in the German shepherd dog and has genetic base. The broomstick-like conformation does not appear to be associated with the presence of canine hip dysplasia and it can therefore be assumed to be a normal anatomic variant.     

Antibiotic responsive ulcerative dermatoses in German Shepherd Dogs with mucocutaneous pyoderma

Mucocutaneous pyoderma is a disease of unknown aetiology affecting mucocutaneous skin and is responsive to antibacterial therapy. It is reported to affect the lips, nasal planum, nares, perioral skin and less commonly, the eyelids, vulva, prepuce and anus. Three cases of mucocutaneous pyoderma are presented. Two of the cases showed ulcerative lesions in the inguinal and axillary regions in addition to more typically reported lesions. Two of the dogs had concurrent atopic dermatitis and the third had clinical signs suggestive of hyper-sensitivity disease. The clinical and histopathological features, differentiation of mucocutaneous pyoderma from discoid lupus erythematosus, and long-term management of mucocutaneous pyoderma are discussed.     

Controlling canine hip dysplasia in Finland.

The aim of the study was to evaluate the Finnish Kennel Club's hip-dysplasia screening and control programs. As a retrospective study, records of hip-dysplasia screening of 69,349 dogs in 22 breeds that were born in 1988-1995 were analyzed and compared to data from prior to 1988. In most breeds, no significant changes in dysplasia prevalence could be found. In English cocker spaniels, golden and Labrador retrievers and Rottweilers a significant decrease - but in boxers, Dobermans, German Shepherd dogs and rough collies a significant increase - in prevalence was detected. In flat-coated retrievers overall prevalence increased - but the prevalence of severe hip-dysplasia decreased significantly during the study period. The present control program has not resulted in fast progress. Selecting against hip-dysplasia cannot be expected to be very effective, when based only on mass selection on phenotypic observations. Predicted breeding values based on progeny testing would probably give better results. Also, breeders' compliance and commitment to programs is not always high and other selection criteria in breeding are thought to be more important. Modern society has high demands for animal welfare and consumer issues, and breeders and kennel societies should pay more attention to health issues in breeding pedigreed dogs.     

德国牧羊犬复孔绦虫种类鉴定和遗传进化分析

为了对采集自3只德国牧羊犬小肠内的复孔绦虫进行种类鉴定和遗传进化分析,通过形态学方法对分离到的虫体进行孔雀绿染色后显微镜观察,并进一步基于线粒体部分基因(pcox1和pnad1)进行PCR扩增和序列分析.显微镜观察结果表明,分离到的虫体形态和内部结构符合犬复孔绦虫的特征.通过对扩增的靶基因序列及其遗传进化分析发现,3个...