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911.
In 1985 and 1986, large-scale natural die-offs of sandhill cranes in Texas were attributed to fusariomycotoxicosis. These birds demonstrated a progressive loss of motor control to the neck, wings, and legs. Based on necropsy and/or histopathology of 31 cranes, the most common lesions involved skeletal muscle and included hemorrhages, granulomatous myositis, thrombosis, and vascular degeneration. Serum chemistry results revealed that levels of creatinine kinase, aspartate aminotransferase, and alanine aminotransferase were above published normals. However, only alanine aminotransferase was higher in clinically affected cranes than in normal cranes collected from the same area. 相似文献
912.
Calcium fluxes were measured, in vivo, in both directions across the ovine reticulorumen wall of four sheep when the luminal potassium concentration was either 30 mmol litre-1 or 90 mmol litre-1. Neither fluxes were affected by an increased potassium concentration although net magnesium absorption was decreased (PO less than 0.05) and the transmural potential difference was increased (P less than 0.01) under these conditions. The results obtained suggest that, unlike magnesium, calcium is transported bidirectionally across ovine ruminal tissue independently of the transmural potential difference across the rumen wall. 相似文献
913.
914.
The spontaneous EEG and somatosensory evoked potentials (SEPs) were examined in chickens before and after electrical stunning using a waterbath stunner. Fifty-four per cent of the birds became epileptic and lost their SEPs, and 17% were non-epileptic and appeared to retain their SEPs. It was concluded that there was a reasonably close association between the presence of epileptiform activity in the EEG and the absence of SEPs following electrical stunning, but that the absence of SEPs could be preferred as an indicator of an effective stun on conceptual grounds. 相似文献
915.
Toxicity of Haemophilus pleuropneumoniae to porcine lung macrophages 总被引:10,自引:0,他引:10
Viable Haemophilus pleuropneumoniae bacteria were toxic for porcine alveolar macrophages in vitro. This cytotoxic effect proved to be dose-related. A cell-free extract of H. pleuropneumoniae, heat-killed bacteria, and a Pasteurella multocida field strain were nontoxic. When macrophages were cultured with H. pleuropneumoniae bacteria in a ratio of 100 macrophages to six bacteria, ultrastructural signs of cellular degeneration were observed within 1 h. This degeneration was observed in macrophages with or without phagosomes containing H. pleuropneumoniae. A cytotoxic substance was filtered from a H. pleuropneumoniae culture in Eagle's minimal essential medium supplemented with Earle's salts (EMEM) and 10% foetal calf serum that was incubated for 10 h at 37 degrees C. This substance was destroyed by heating at 65 degrees C for 30 min. Macrophages were less susceptible to the toxic effect of H. pleuropneumoniae when serum of convalescent pigs was added. 相似文献
916.
917.
918.
A 3‐year‐old Burmese cat was presented with a history of nonresolving crusted and papular lesions of the face and prior treatment with prednisolone. Skin biopsies revealed typical pox lesions with hyperplasia and ulceration of the epidermis and eosinophilic cytoplasmic inclusion bodies in the epidermal cells. In the upper dermis there was prominent diffuse mast cell infiltration and mild neutrophilic and eosinophilic inflammation. Rare cytoplasmic inclusion bodies were also present in swollen endothelial cells of dermal venules, which showed no other degenerative changes. Histological diagnosis was confirmed by electron microscopic evidence of pox virus particles in inclusion bodies of epidermal cells. The lesions resolved within 6 weeks with systemic antibiotic therapy and supportive care. A 2‐year‐old domestic short‐haired cat was presented with multiple disseminated papular and ulcerative pox lesions with central eschar over the entire body. Histologically, large epidermal inclusion bodies (up to 6 μm in diameter) were present. Widespread haemorrhage and vascular wall necrosis was visible in the dermis and subcutis. Some subcutaneous vessels showed neutrophilic vasculitis. In addition to diffuse dermal neutrophilic and eosinophilic inflammation, a lymphohistiocytic panniculitis was also present. The cat died as a result of massive haemorrhage and lymphedema, despite supportive care. Funding: Self‐funded. 相似文献
919.
M Contrepois H C Dubourguier A L Parodi J P Girardeau J L Ollier 《Veterinary microbiology》1986,12(2):109-118
Three strains of Escherichia coli with a common surface antigen, 31a, capable of adhering to calf enterocytes in vitro were compared to reference strains of septicaemic E. coli (RVC 330 and vir E. coli). The surface antigen 31a was present in the RVC 330 reference strain. E. coli vir had a surface antigen which was not present in E. coli 31a or E. coli RVC 330. The RVC 330 and vir reference strains also adhered to calf enterocytes in vitro. Oral infection of calves not receiving colostrum with E. coli 31a was generally followed by septicaemia and death in less than 48 h. Post-mortem examination revealed pneumonia and oedema of the kidneys and gall bladder. Oral infection of calves receiving colostrum had no effect, but intravenous inoculation produced arthritis within 15 days. The comparison of these results with those previously described by other workers did not lead to the identification of pathognomonic characteristics, which could be clearly correlated with properties specific to E. coli 31a. It is suggested that, like ColV and vir, antigen 31a may be a virulence marker for certain strains of bovine septicaemic E. coli. Furthermore, the 31a antigen appears to be carried on a plasmid. 相似文献
920.