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981.
982.
983.
Forty-six isolates of Taylorella equigenitalis were analysed by pulsed-field gel electrophoresis (PFGE) after separate digestion of the genomic DNA with ApaI and with NotI. The isolates had been obtained from horses in six European countries and were classified into 18 genotypes. In Belgium, 2 genotypes were detected in 2 isolates, in England 9 among 15, in Finland 2 in 2, in France 2 among 10, in Sweden 3 among 5, and in Switzerland 3 among 12. Two English isolates and 4 French isolates gave identical PFGE profiles to those of Kentucky 188 from the United States. A common genotype was found in 5 isolates from Belgium and England and also in 10 isolates from France and Switzerland. The analysis of genomic DNA from 12 isolates of T. equigenitalis obtained from male horses in France, Sweden and Switzerland gave no evidence of a sex-related difference in the genomic DNA. Genomic DNA from 11 streptomycin (STM)-susceptible isolates obtained in Sweden and Switzerland were classified into four genotypes by PFGE. Each of the six genotypes determined among the 17 isolates from these two countries had single phenotypes for resistance or susceptibility to STM.  相似文献   
984.
Mycotoxic nephropathy was induced in 18 young pigs by diets contaminated with strains of Aspergillus ochraceus containing ochratoxin A (OTA) and penicillic acid (PA) at levels corresponding to those naturally encountered in animal feeds in Bulgaria. Haematological and biochemical parameters, as well as the morphological and ultrastructural changes in various internal organs, and especially in the kidneys, were examined at different stages of development of the disease. A mottled surface of the kidneys was only seen in pigs exposed to a mouldy diet containing 180 ppb OTA for 3 months, but microscopic lesions, as well as changes in various haematological and biochemical parameters, were observed in all groups exposed to the same mouldy diet containing only 90 or 180 ppb OTA. Histological examination showed two types of change: degenerative changes affecting the epithelial cells of the proximal tubules, which predominated at the initial stage, and proliferative changes in the interstitium, which predominated at the later stage of the disease. Telangiectasis and lymph stasis were also seen, as well as degenerative changes in the capillary endothelium. The characteristic renal lesions were similar to those observed in spontaneous cases of mycotoxic porcine nephropathy in Bulgaria, but they were a little different from the classic Danish porcine nephropathy. The enhanced toxicity of OTA in our study may be due to a synergistic effect between OTA and PA or to some other unknown metabolites produced by the same ochratoxinogenic strains of A. ochraceus.  相似文献   
985.
Lymphangiosarcoma of the pulmonary pleura was found to be the cause of persistent chylothorax in an eight-year-old, intact male golden retriever. After a two-month course of medical management, a lymphangiogram and thoracic duct ligation were performed with the objective of decreasing further effusion. At surgery, gross lung pathology was biopsied and yielded a histopathological diagnosis of pulmonary pleural lymphangiosarcoma. A relatively rare tumor, lymphangiosarcoma of the pulmonary pleura has not previously been documented as a source of chylothorax in the dog.  相似文献   
986.
An analysis of the informative content of sequence stretches on the foot-and-mouth disease virus (FMDV) VPI gene was applied to two important viral serotypes: A and O. Several sequence regions were identified to allow the reconstruction of phylogenetic trees equivalent to those derived from the whole VPI gene. The optimal informative regions for sequence windows of 150 to 250 nt were predicted between positions 250 and 550 of the gene. The sequences spanning the 250 nt of the 3' end (positions 400 to 650), extensively used for FMDV phylogenetic analyses, showed a lower informative content. In spite of this, the use of sequences from this region allowed the derivation of phylogenetic trees for type A and type O FMDVs which showed topologies similar to those previously reported for the whole VP1 gene. When the sequences determined for viruses isolated in Argentina, between 1990 and 1993, were included in these analyses, the results obtained revealed features of the circulation of type A and type O viruses in the field, in the months that preceded the eradication of the disease in this country. Type A viruses were closely related to an Argentinean vaccine strain, and defined an independent cluster within this serotype. Among the type O viruses analysed, two groups were distinguished; one was closely related to the South American vaccine strains, while the other was grouped with viruses of the O3 subtype. In addition, a detailed phylogeny for type A FMDV is presented.  相似文献   
987.
Measurements were made of the extent of sole and white line lesions on the claws of 115 Holstein-Friesian cows on at least three and at most 16 occasions, and some cows were followed up to their third lactation. All the measurements were made between 12 weeks before calving and 45 weeks after calving. In total, 1016 repeated observations were made. Correlations were calculated between pairs of claws, between types of lesion (sole and white line), and between pairs of the different measurements (number of lesions, proportion of the claw affected, maximum severity score and proportion of the claw affected weighted for severity). The outer hind claws had the greatest extent of lesions of both types. Spearman correlation coefficients and confidence intervals measured the strength of the association. All the associations between claws were positive, suggesting that the lesions did not occur in isolation. Sole and white line lesions were not associated at individual observation points. Lesions on the left and right claws were markedly similar, except for sole lesions on the two inner hind claws, and for white line lesions on the two outer hind claws.  相似文献   
988.
The clinicopathological features of an unusual case of a five-month-old male Spanish mastiff, which was presented with clinical signs indicative of severe hepatic failure, are reported. Fluid replacement therapy, colloid plasma expanders, antibiotics and diuretic drugs were unsuccessful in improving the animal's general condition, and euthanasia was elected by the owner. On necropsy, ascites and severe cirrhosis, with extensive periacinar necrosis, was found. Cirrhosis is a rare lesion in young dogs. The most common causes are circulatory disturbances, hereditary metabolic disorders or poisoning, such as aflatoxicosis and anticonvulsant therapy. The possible involvement of canine adenovirus in this case is discussed.  相似文献   
989.
990.
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