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991.
OBJECTIVE: To investigate the relationship between diet, growth rate and the presence of caudal cervical malformation in Doberman puppies. DESIGN: A prospective study of 15 Dobermann puppies from three unrelated litters, aged from 0 to 16 weeks. PROCEDURE: The growth rate in terms of body weight gain and increase in ulna length were measured weekly for all puppies. In addition the nutritional quality of the diets was assessed. Radiographs of the cervical spine were taken at 6 and between 12 and 16 weeks of age and examined for the presence of caudal cervical vertebral malformation. A mixed model for repeated measures data was used to investigate the relationship between the growth rate of the puppies and the fixed effects age, dam, diet, gender and presence of caudal cervical malformation. RESULTS: Five of the puppies had changes consistent with caudal cervical malformation. The diets fed were either balanced or transiently deficient in protein, calcium, phosphorus and/or magnesium. There was no significant association between growth rate and the variables dam, gender and the presence of caudal cervical vertebral malformation. There was no significant association between diet and increase in ulna length, but a trend existed between body weight gain and the feeding of a balanced diet (P = 0.0672). CONCLUSION: Caudal cervical vertebral changes can be detected radiographically as early as 6 weeks of age in some Dobermann puppies. A balanced diet and growth rate are not significant factors in its initial development.  相似文献   
992.
Proliferative cutaneous lesions are frequently encountered in examination of avian species. Tumors of the skin have been reported in many bird species, although comparatively less is known about the incidence of integumentary neoplasia in nondomesticated species than in production or companion species. An adult male, 9-yr-old, captive-bred barn owl (Tyto alba) was presented for examination of a proliferative skin mass of several months' duration on the left wing. An excisional biopsy was performed, and the owl recovered uneventfully. Light microscopic examination of tissue sections of the mass revealed a focal, unencapsulated, well-demarcated, multiloculated mass that consisted of variably sized cystic spaces lined by stratified squamous epithelium and containing concentric laminations of keratin and foci of feather differentiation. A histopathologic diagnosis of feather folliculoma was made. This neoplasm has not previously been described in owls. Its incidence and documentation are significant in that this neoplasm should be considered as a differential diagnosis of proliferative skin lesions in this raptorial species.  相似文献   
993.
994.
Ten common kestrels (Falco tinnunculus) were used for this falcon herpes vaccine experiment. Four kestrels were subcutaneously given 1 ml of an attenuated falcon herpesvirus that had originally been isolated from the liver of an American prairie falcon (Falco mexicanus). This virus was then passaged 100 times on chicken embryo fibroblast cells (CEF-cells). Another 4 kestrels were given subcutaneously an inactivated falcon herpesvirus vaccine derived from the same American field strain. This vaccine was concentrated, inactivated by heat and betapropiolactone and emulsified in complete Freund's adjuvans. Two further kestrels served as controls and were not vaccinated. Twenty-one days after vaccination, all 10 kestrels were challenged with passage 3 of the American falcon herpesvirus. The 2 control kestrels died 6 days after challenge and 3 of those given the inactivated herpes vaccine died 9 days after challenge, with typical lesions of herpesvirus inclusion body hepatitis. Before the vaccination experiment, all 10 kestrels were free of serum neutralising antibodies to the falcon herpesvirus. Twenty-one days after vaccination, all 4 kestrels vaccinated with the attenuated vaccine, and one vaccinated with the killed vaccine, had seroconverted, having shown no symptoms to the challenge with a low passage virulent American herpesvirus strain. Following the challenge their antibody titres to falcon herpesvirus increased. No herpesvirus was isolated from any of the cloacal swabs taken during this experiment, indicating that there is no danger for any other birds from the attenuated herpesvirus vaccine. This experiment clearly shows that an attenuated falcon herpesvirus vaccine can protect kestrels from fatal inclusion body hepatitis.  相似文献   
995.
The capacitation process of sperm cells involves complex changes in the composition and orientation of molecules at the surface of the sperm cell. Here we focus on the lipid architecture in the sperm plasma membrane and demonstrate that the sperm plasma membrane is not static but is an extremely dynamic structure. Advanced fluoroscopic techniques enabled continuous monitoring of lipid organization in living cells and extremely rapid lipid movements were observed. The orientation of lipids in the sperm plasma membrane changed under capacitative treatments, was found to be sensitive for temperature and also changed upon binding of sperm cells to the zona pellucida. The changes in membrane properties coincided with an activation of protein kinases resulting in tyrosine phosphorylation of specific plasma membrane proteins. The detected membrane changes relate to intrinsic membrane properties such as fluidity, permeability, adhesiveness and fusibility. We think that these results may provide a physiological basis for new assays, able to discriminate between functional and non-physiological sperm cells.  相似文献   
996.
Escherichia coli O26:K60, with genetic attributes consistent with a potentially human enterohaemorrhagic E. coli was isolated from the faeces of an eight-month-old heifer with dysentery. Attaching and effacing lesions were identified in the colon of a similarly affected heifer examined postmortem, and shown to be associated with E. coli O26 by specific immunolabelling.  相似文献   
997.
An experiment was carried out in 1997 to test the efficacy of an isolate of the microfungus Duddingtonia flagrans against free-living stages of horse strongyles under conditions in the field and to assess the eventual effect of the fungus on the normal degradation of faeces. Faecal pats were made from faeces of a naturally strongyle infected horse, which had been fed fungal material at a dose level of 106 fungal unit/kg bwt. Control pats without fungi were made from faeces collected from the same animal just before being fed fungi. Faecal cultures set up for both groups of faeces to monitor the activity of the fungus under laboratory conditions showed that the fungus significantly reduced the number of infective third-stage larvae (L3) by an average of 98.4%. Five faecal pats from each batch of faeces were deposited on pasture plots at 3 times during spring-summer. The herbage around each pat was sampled fortnightly to recover L3 transmitted from faeces. The results showed that the herbage infectivity around fungus-treated pats was reduced by 85.8-99.4%. The remaining faecal material at the end of each sampling period was collected, and the surviving L3 were extracted. Significantly fewer larvae were recovered from the fungus-treated pats. Analysis of wet and dry weight of the collected pats, as well as their organic matter content, were performed to compare the degradation of faeces of both groups. The results indicated that the presence of the fungus did not alter the degradation of the faeces.  相似文献   
998.
999.
The metabolic syndrome is a set of risk factors for the development of type 2 diabetes, atherosclerosis, coronary heart disease and stroke in human beings. The term has recently been applied to dogs that exhibit components of the human metabolic syndrome, specifically visceral obesity, hypercholesterolaemia, hypertriglyceridaemia, hypertension and fasting hyperglycaemia. Obese dogs, like obese humans, are known to develop resistance to the glucose-lowering effects of insulin, and develop increased circulating concentrations of triglycerides, cholesterol and blood pressure. Unlike humans, however, obese dogs do not develop fasting hyperglycaemia or atherogenic hyperlipidaemia. Importantly, there is no evidence that dogs develop type 2 diabetes. Atherosclerosis, coronary heart disease and stroke are rare and not known to be associated with obesity in dogs. On the basis of current knowledge, the use of the term ‘metabolic syndrome’ in dogs does not appear to have merit.  相似文献   
1000.
Inhalant exposure to airborne irritants commonly encountered in horse stables is implicated in the pathogenesis of inflammatory airway disease (IAD) and recurrent airway obstruction (RAO), non‐infectious, inflammatory pulmonary disorders that impact the health and performance of horses across all equine disciplines. IAD and RAO have overlapping clinical, cytological, and functional manifestations of the pulmonary response to organic dust and noxious gases encountered in the barn environment. Study of these diseases has provided important but incomplete understanding of the effect of air quality upon the respiratory health of horses. In this review, the principles of particulate exposure assessment, including health‐related aerosol size fractions and size‐selective sampling, the factors influencing air quality in equine environments, and the effect of air quality on the equine respiratory tract are discussed. The objective of this review is to provide the reader with a summary of the most common chronic inflammatory airway diseases in the horse and the principles of air sampling that are essential to the planning, interpretation, and assessment of equine respiratory health‐related exposure studies.  相似文献   
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