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Summary The study reported in the present paper discusses the clinical and histological picture of bovine demodecosis and the morphology of Demodex mites as seen in four cows suffering from generalized demodecosis. There were no clinical signs of other skin affections. Changes in both the number and the appearance of visible skin lesions were seen and related to the level of nutrition and the exposure to sunshine of the cattle. Histological sections of some skin nodules showed the presence of mite colonies in the hair follicles. Only adults were seen in the sebaceous glands. Microscopical study of the morphology of the mites revealed the presence of two types of demodicids in the skin lesions and three types from epilated eyelashes. Morphological criteria are presented to aid in identification of species and of life stages.  相似文献   
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Summary Pasteurella haemolytica causes two distinct disease syndromes in sheep. P. haemolytica biotype A causes septicaemia in young lambs and pneumonia in all ages of sheep. Biotype T produces an acute systemic disease affecting principally the upper alimentary tract and lungs in young adult sheep. The bacteriology, epidemiology and clinical and necropsy findings of the two diseases are described and the current situation regarding their experimental reproduction and immunology is reviewed.  相似文献   
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Animal feed-additive samples (n = 300) were examined for the presence of salmonellae, using the selenite-F broth-enrichment method followed by subculturing on Salmonella-Shigella and brilliant green agar with sulfadiazine selective agar plates. Samples consisted of a variety of feed additives: 119 bone meal samples, 77 meat meal samples, 40 fish meal samples, and 64 miscellaneous meal samples. Results of examination found 49 (41.2%) of the bone meal samples, 6 (7.8%) of the meat meal samples and 2 (5%) of the fish meal samples contained salmonellae. Of 57 isolates representing 24 serotypes, 4 most frequently isolated serotypes were Salmonella meleagridis (35.1%), Salmonella tennessee (7%), Salmonella chester (5.2%), and Salmonella senftenberg (5.2%). This study shows a high Salmonella-contamination rate of bone meal compared with meat meal and fish meal samples. Of 12 known positive bone meal samples that were examined, 100% of 25-g samples, compared with 70% to 100% of 2.5-g samples and 30% to 90% of 0.25-g samples and 30% to 90% of 0.25-g samples, were positive for salmonellae.  相似文献   
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Quantitative and qualitative bacterial assays were performed on the skin of 15 normal and 32 seborrheic dogs. Nonionic detergent scrubs were made on areas demarcated by glass sidearm cylinders. Quantitative analysis was accomplished by the serial dilution technique, and the bacteria were identified by individual and colonial morphology and by enzyme production. Areas measured on control dogs had a markedly lower total bacterial count than similar areas measured on seborrheic animals. Control dogs had a flora consisting primarily of coagulase-negative cocci, whereas seborrheic dogs usually had a cutaneous flora composed primarily of Stahylococcus aureus, coagulase-positive.  相似文献   
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