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81.
Four at-risk Highland ponies on the same premises all retained their fetal membranes in the same breeding season. The ponies were treated with a combination of oxytocin, infusion and distension of the allantochorionic sac with fluid, gentle traction in one case, and supportive therapy. The possible causes of the condition were investigated with clinicopathological tests and analyses of the herbage for its species composition and fungal contamination. No obvious possible causative abnormalities were identified apart from a low total serum calcium level in one case. No fescue grass was found and no pathogenic fungi were detected. 相似文献
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1. Nine different sites at a poultry processing plant were selected in the course of a hazard analysis to investigate the degree of microbial cross‐contamination that could occur during processing and the effectiveness of possible control measures.
2. At each site, carcases, equipment or working surfaces were inoculated with a non‐pathogenic strain of nalidixic acid‐resistant Escherichia coli K12; transmission of the organism among carcases being processed was followed qualitatively and, where appropriate, quantitatively.
3. The degree of cross‐contamination and the extent to which it could be controlled by the proposed measures varied from one site to another. 相似文献
85.
One hundred ovine and 100 bovine carcasses in two abattoirs were sampled just after dressing for the presence of Yersinia enterocolitica, Listeria monocytogenes and motile aeromonads. Yersinia enterocolitica was not isolated and only two samples were positive for Listeria spp. In both cases, the Listeria species were not normally pathogenic to man. In contrast, motile aeromonads were isolated from 81% of ovine and 35% of bovine carcasses. 相似文献
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S Chakraborty R Knoche H Schulze DC Rubie D Dobson NL Ross RJ Angel 《Science (New York, N.Y.)》1999,283(5400):362-365
Rates of cation diffusion (magnesium, iron, and nickel) have been determined in olivine and its high-pressure polymorph, wadsleyite, at 9 to 15 gigapascals and 1100 degrees to 1400 degreesC for compositions that are relevant to Earth's mantle. Diffusion in olivine becomes strongly dependent on composition at high pressure. In wadsleyite, diffusion is one to two orders of magnitude faster than in olivine, depending on temperature. Homogenization of mantle heterogeneities (chemical mixing) and mineral transformations involving a magnesium-iron exchange will therefore occur considerably faster in the transition zone than at depths of less than 410 kilometers. 相似文献
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S L Young R S Hudson D F Walker 《Journal of the American Veterinary Medical Association》1977,171(7):643-648
Eleven bulls were determined to be impotent due to vascular shunts from the corpus cavernosum penis to the extracorporeal circulation. Clinically, the bulls were unable to achieve erection when stimulated with an electroejaculator and in natural breeding trials. The vascular shunts were located by serial contrast radiography of the corpus cavernosum penis. Surgical correction of the shunts was attempted in 8 of the bulls by wedge resection of the tunica albuginea. In 4 bulls, the surgical correction was successful and the bulls were returned to service. 相似文献