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Karl A.Dawson 《中国家禽》2001,23(9):32-35
1 简介霉菌毒素是霉菌代谢的次级产物,这种物质很可能在饲料的制造与贮存过程中污染到饲料。目前已知至少有300种以上霉菌代谢产物会使动物及人类中毒,全世界谷物中有25%受到霉菌毒素的污染,而且达到可量测的浓度。在这些毒素中,已知有很多种物质明显影响动物的健康,对动物生产造成重大影响。2 霉菌毒素的产生在自然状态下霉菌毒素的产生是一个全球性问题,但是世界上某些特定地区霉菌毒素产生的情形比其他地区频繁。在较冷或气候较温和的地区,例如加拿大、美国的北部及多数欧洲国家,黄曲霉毒素并不是主要问题,除了进口的饲料原料… 相似文献
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A method was developed to follow a lactic acid bacterial strain, Enterococcus faecium Cernelle 68, with respect to adhesion, multiplication, colonization, and persistence in the digestive tract of mink. Also the spread of the strain in the cage was examined. When adding 5 x 10(9) c.f.u. of a rifampicin resistant mutant per kg feed, high viable counts were registered throughout the digestive tract, apart from the oesophagus. Counts were increasing in the aboral direction, suggesting some multiplication in the intestine. It was possible to detect the strain in the intestinal tract 4 days after discontinuation of administration. Neither culture nor scanning electron microscopy gave evidence to suggest that E. faecium Cernelle 68 adhered to the mucosa. The spread of the E. faecium strain was observed in the environment. Counts of E. coli, lactobacilli, staphylococci, and clostridia were low, and none of these bacteria were constant findings. 相似文献
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Ivar V gsholm Hans Olav Djupvik Finn Victor Willumsen Anne Marie Tveit Karl Tangen 《Preventive veterinary medicine》1994,19(3-4):277-290
A case-control study is reported of 57 holdings (holdings in which salmon are raised in sea-water) with infectious salmon anaemia (ISA) and 61 holdings without ISA, together with a follow-up study of the control holdings, during 1988–1990. Generally the identified risk factors implied poor biosecurity since passive transmission (proximity to other ISA holdings) and active transmission (management practices which increased exposure to foreign biological material) were found to be major risk factors. The findings indicated that ISA was spread by infected live salmon or infected biological material i.e. animal waste or discharge from normal operations and slaughter. The findings also indicated that decreased host resistance could be important, but these results could be also be explained by a misclassification bias. Moreover, the findings indicate that a prompt eradication policy and improved biosecurity would be important means of controlling ISA. 相似文献
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Jandrey KE Smarick SD Burkitt JM Labelle P Mohr FC Kittleson MD 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2005,19(4):602-605
A young adult, 28 kg, intact female Siberian husky-mixed breed dog was presented to the Veterinary Medical Teaching Hospital (VMTH) Emergency Service for evaluation of a dysrhythmia and an abnormal cardiac structure. The dog had been adopted from an animal shelter approximately 3 months before presentation. The dog occasionally showed exercise intolerance, and the owners suspected that she had impaired vision. Initial clinical signs appeared 2 days before presentation during strenuous activity—the dog uncharacteristically stopped and lay down while tachypneic. The dog produced dark liquid feces and was lethargic and anorexic overnight. 相似文献