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991.
The epidemiology of wildebeest-derived malignant catarrhal fever in South Africa differs from the worldwide accepted pattern. Here the occurrence of the disease is often not related to close contact between cattle and wildebeest, and most cases are observed during late winter and spring, when wildebeest calves are 8-10 months old. This is in contrast to the situation in Kenya and Tanzania, where most cases are encountered during autumn, when wildebeest calves are 3-4 months old. 相似文献
992.
Characterization and purification of the F17 adhesin on the surface of bovine enteropathogenic and septicemic Escherichia coli 总被引:13,自引:0,他引:13
P F Lintermans P Pohl A Bertels G Charlier J Vandekerckhove J Van Damme J Schoup C Schlicker T Korhonen H De Greve 《American journal of veterinary research》1988,49(11):1794-1799
The F17 antigen from bovine enterotoxigenic Escherichia coli strain (E coli 25KHO9), which adhered to calf intestinal villi, was isolated. An enterotoxin-negative derivative (25KHO9st) was used for further studies. Using an immunogold-labeling technique, the F17 antigen was characterized as a fimbrial protein. Pure fimbriae with a subunit molecular weight of 20,000 were obtained by homogenization and use of a sucrose gradient. The adhesion of E coli 25KHO9st was mediated by the F17 fimbriae, as both F17 antibodies and F17 protein blocked the adhesion of the strain 25KHO9st. The F17 fimbriae were serologically distinct from K88, K99, F41, and 987P fimbriae and did not agglutinate bovine, ovine, guinea pig, human, or chicken erythrocytes. Peptide fingerprint analysis revealed F17 and F(Y) adhesins to be homologous, if not identical. 相似文献
993.
K A Bruner S D Van Camp 《Veterinary Clinics of North America: Food Animal Practice》1992,8(2):331-345
Physical examination requires very little equipment or expense and is an effective means of obtaining valuable information concerning fertility. Thorough evaluation of the reproductive system provides important information often unattainable by any other means. Disease processes, congenital abnormalities, injuries, management errors, and many other factors can be identified. No segment of the examination should be overlooked, as each part is important. The time invested in evaluating the male reproductive system is rewarded with a more complete and accurate assessment of the breeding male. 相似文献
994.
995.
L. Vellenga Th. Wensing H. J. A. Egberts J. E. Van Dijk J. M. V. M. Mouwen H. J. Breukink 《Veterinary research communications》1988,12(6):481-489
The permeability of the intestine of specific pathogen free piglets was investigated by measuring the concentration of 125-I in the blood after oral administration of 125-I polyvinylpyrrolidone (125-I PVP, MW=40 000 Da) and the concentration of 131-I in the faeces after intravenous administration of 131-I porcine albumin (131-I PA, MW=68 000 Da). The tests were performed one day before and up to two days after the piglets were infected with the Miller strain of transmissible gastroenteritis (TGE) virus. Biopsies of the jejunum were taken at the end of the experiment and blood samples were taken six-hourly. The piglets became anorexic and had diarrhoea 12 hours after infection; the packed cell volume decreased and the concentrations of urea and total serum proteins increased slightly after infection. However, the marked villous atrophy was not accompanied by an increased permeability of the intestine to PVP or PA. 相似文献
996.
Triacylglycerols are the most concentrated storage form of energy for the mammalian organism. These lipids are synthesized and secreted by the liver and serve as a fuel for other tissues. This paper presents a brief review of the regulation of hepatic triacylglycerol synthesis and secretion. Particular attention will be given to the dissociation of the synthesis of triacylglycerols from that of the metabolically closely related nitrogenous phospholipids. Recent evidence is presented which suggests that triacylglycerol synthesis (and secretion) is regulated, at least partially, at the diacylglycerol branchpoint. 相似文献
997.
998.
999.
J. E. Van Dijk A. Fledderus J. M. V. M. Mouwen C. Holzhauer 《Veterinary research communications》1988,12(1):47-59
The significance of food allergy as a primary cause for gastrointestinal disturbances in domestic animals, especially calves and piglets, is discussed. The immunological backgrounds and pathogenesis are described in some detail. The clinical and pathological manifestations in animals are related to those in man. Diagnostic possibilities, therapy and prevention, as far as known in animals, are mentioned and, based on human experiences, further extensions are proposed. 相似文献
1000.