Hemophilia in dogs, with special reference to hemophilia A among German shepherd dogs in Denmark. II: Clinical study, therapy and prophylaxis

Clinical data, pedigrees, screening tests (APTT, PT and TT) and specific tests (VIII:C, VIIIC:Ag, VIIIR:Ag and IX:C) were used to diagnose hemophilia A (classical hemophilia) in two colonies of German Shepherd dogs in Denmark. The affected individuals in both colonies were males, and they descended from a common, hemophilic ancestor. All observations were in accordance with X-linked, recessive inheritance. Therapeutic and prophylactic measures are discussed.     

Haemophilia A in German shepherd dogs

Haemophilia A was diagnosed in 14 male German shepherd dogs. Factor VIII: coagulant (FVIII:C) activities ranged from 1.13% of a normal canine plasma pool. von Willebrand's factor antigen values were normal or increased in all 9 of these dogs which were tested. Twelve of these dogs had a common maternal grandsire. Five dogs had exhibited no tendency to bleed (when tested between 2 to 23 months of age). They were tested because of pedigree links with clinically affected animals. Common clinical signs in the latter dogs included: bleeding from the mouth, subcutaneous and intramuscular haematomas and lameness. Since these dogs usually had a mild to moderate deficiency of FVIII:C, they may survive to adulthood without exhibiting clinical signs severe enough to necessitate veterinary attention.     

Immunologic study of systemic aspergillosis in German shepherd dogs

Data are presented from a series of eight cases of disseminated canine aspergillosis (A. terreus) in German Shepherd dogs referred to Murdoch University Veterinary Hospital. Immunoglobulin determination revealed depression of serum IgA (cases 1 and 5) and IgM (case 2) levels and elevated levels of IgG in all cases. Total complement activity (CH50) and complement components tests, (C3, C4) were present in normal amounts in all cases. Using agar gel diffusion, serum antibody to A. terreus was found in only one case and aspergillus antigenaemia in two of the remainder. Lectin transformation of lymphocytes in two dogs was found to be depressed relative to normal controls in case 1 and initially in case 2. Two dogs failed to respond to the intradermal injection of A. terreus antigen.     

A degenerative myelopathy in young German shepherd dogs

Two young male German shepherd dogs, six and seven months old, were evaluated for progressive hindlimb ataxia and paresis. Both dogs were found to be thin and poorly muscled on physical examination, and on neurological examination, the lesions were localised to the spinal cord between T2 and L4. Microscopical examination of the spinal cords demonstrated widespread axonal degeneration similar to that seen in aged German shepherd dogs with chronic degenerative radiculomyelopathy (CDRM), although the distribution of these changes was not identical to CDRM.     

Computed tomographic pelvimetry in German shepherd dogs

Pelvimetry was performed on a computed tomographic scanner using dorsal and lateral scout-view images of 10 adult German shepherd dogs. The vertical and transverse diameters of the pelvis were measured and the pelvic inlet and pelvic outlet areas were also calculated. No significant correlations between the pelvic measurements and body weight, age and sex were found. Although the conjugata vera, diameter verticalis, diameter sacralis, sagittal diameter and the distance between the two medial tubera ischiadica were longer in females, no significant statistical difference was found between male and female animals for all measurements. It is proposed that the computed tomographic pelvimetry should be preferred for the sensitive measurements when the normal standards are determined for different animal species and the cost is reduced to an acceptable level.     

Echocardiographic indices in normal German shepherd dogs

Sixty clinically normal German shepherd dogs, 31 males and 29 females, ranging in age from 1 and 5 years and with a body weight ranging from 22 to 37.2 kg, were examined by the two-dimensional mode, M-mode, and Doppler echocardiography. In Doppler mode, the mitral valve flows were obtained, where the aim was to determine the velocity peaks and ratios of the E and A waves and the mitral E wave deceleration time. The velocity peaks were obtained for the tricuspid, pulmonary and aortic valves. On the left ventricular outflow tract flow, the time velocity integral and aortic cross-sectional area was used to calculate the cardiac output. A statistically significant correlation with the body weight was found for the systolic left atrial and diastolic aortic diameter on two-dimensional mode. On M-mode, there was a significant correlation between the body weight and the systolic left atrium and diastolic aortic dimension, systolic and diastolic left ventricular, septal and posterior wall dimensions. Doppler echocardiography showed that there was no significant correlation between the body weight and the mitral, tricuspid, pulmonary and aortic valves flows. These results demonstrate that it is important to know the normal echocardiographic values for German shepherd dogs because there are some characteristics peculiar to this particular breed. The data obtained is expected to be helpful for studies on small animal cardiology.     

Medullary trichomalacia in 6 German shepherd dogs

Medullary trichomalacia is the name proposed for a hair shaft abnormality that was recognized in 6 German shepherd dogs. Affected dogs had multifocal areas of broken hairs, especially on the dorsolateral trunk. Microscopic examination of hair shafts revealed focal areas of loss of architecture, swelling, and apparent softening of the medulla, followed by longitudinal (length-wise) splitting and breakage of the hair shaft. No cause could be found. Affected dogs were otherwise healthy, and apparent spontaneous recovery was the usual outcome. Relapses may occur.     

A moderately severe expression of classical hemophilia in a family of german shepherd dogs

A kindred of German shepherd dogs with a moderately severe form of classic hemophilia was studied. The propositus was presented at five months of age because of a persistent hind limb lameness and swelling of the left stifle joint. Unclotted blood was aspirated from the swelling. A brother of this dog's dam had been diagnosed as a hemophiliac.Hemostatic tests were performed on the propositus and on ten available related dogs. On the basis of pedigree analysis, sex and specific factor VIII related activity levels in their plasmas, the dogs were classified as affected, carriers, or unaffected. The propositus and one male relative were identified as classical hemophiliacs and were classified as moderately severely affected on the basis of apparent bleeding tendency and factor VIII procoagulant levels (FVIII:C 8-10% of normal). The propositus' signs were confined to those of lameness and joint soreness and postmortem lesions were confined to a few joints (hemarthrosis). The affected male relative was asymptomatic up to the time of euthanasia (three months of age) and did not have postmortem lesions attributable to hemophilia.Although classic hemophilia (particularly in large breeds of dogs) is often a severe clinical disease, more moderate forms of the disease do occur. Such forms may be more difficult to recognize early in life.     

Spontaneous laryngeal paralysis in four white-coated German shepherd dogs

Four cases of spontaneous laryngeal paralysis in juvenile white-coated German shepherd dogs are described. The presenting signs were typical for laryngeal paralysis, with stridor present in all four cases. Laryngoscopy revealed bilateral laryngeal paralysis in three cases, and unilateral paralysis in one. Concurrent megaoesophagus was also identified in one dog. All dogs underwent surgical treatment for laryngeal paralysis. Euthanasia was performed in one case due to intractable regurgitation and aspiration pneumonia. A possible association with white coat colour is discussed.     

Age-associated changes in the immune system of German shepherd dogs

In order to look into the ageing of the canine immune system we investigated age-related changes and associated gender-related differences in parameters of innate and acquired immunity in German Shepherd dogs. We obtained the following findings: white blood cell counts, peripheral blood lymphocytes, lymphocyte proliferative activity and interleukin-2 (IL-2) serum concentrations were significantly lower in the group of old animals, whereas the concentrations of gamma-globulins and the functional activity of the complement system were significantly higher in the elderly. Phagocytic and bactericidal activity of polymorphonuclear cells, as well as their 'killing function,' the serum cytokine-like activities of tumour necrosis factor-alpha and the plasma concentrations of immunoglobulin G, as well as of alpha- and beta-globulins, were not significantly affected by age, whereas natural killer-cell activity and the serum cytokine-like activities of IL-1 were significantly higher only in the group of female old animals. With regard to gender-related differences, lymphocyte proliferative activities as well as plasma concentrations of alpha-globulin were significantly higher in the group of female animals, whereas the absolute numbers of segmented neutrophils were significantly lower. Species analogies with regard to ageing as presumed to exist between man and laboratory rodents also seem to be applicable to the dog. The observed age-related changes in the canine immune system are probably among the main causes for the multimorbidity of old age, affecting life expectancy and mortality in the dog and should be recognized and considered by the attending veterinarian.     

Serum alpha-tocopherol concentrations in German shepherd dogs with chronic degenerative radiculomyelopathy

The concentration of serum alpha-tocopherol was measured in German shepherd dogs with chronic degenerative radiculomyopathy, and in German shepherd dogs and dogs of other breeds unaffected by the condition. The mean concentration was significantly higher in German shepherd dogs with the condition than in other breeds of dog unaffected by it, but it was not significantly higher than in unaffected German shepherd dogs. Estimates of components of variance indicated that the concentration varied more widely in individual affected dogs than in unaffected dogs, irrespective of breed. These results suggest that chronic degenerative radiculomyopathy in German shepherd dogs is unlikely to be due to uncomplicated vitamin E deficiency.     

全基因组关联分析在德国牧羊犬髋关节发育不良研究中的应用现状

犬髋关节发育不良(canine hip dysplasia,CHD)是犬常见的骨科疾病,传统放射学诊断对降低CHD发病率的作用有限,而基因诊断技术则可以有效促进CHD的育种改良。全基因组关联分析(genome wide association study,GWAS)是一种全基因组范围内的遗传标记的检测技术,对复杂性状功能基因的鉴定十分有效,已成为挖掘畜禽复杂疾病和性状遗传的重要方法。随着犬全基因组测序的完成以及犬不同密度SNP芯片的商业化,GWAS已经成为CHD致病基因筛选的一个重要手段。本文综述了GWAS的定义与影响因素,CHD在国外的育种现状及GWAS在德国牧羊犬中的研究进展。