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31.
抑制素免疫山羊卵巢对外源性促性腺激素的反应 总被引:2,自引:0,他引:2
用重组绵羊抑制素α亚单位在不发情季节主动免疫 4 0只波尔山羊。免疫前和免疫后用马的绒毛膜促性腺激素 (eCG)或猪的卵泡刺激素 (pFSH)处理。排卵通过超声波检测 ,胚胎用非手术法回收。试验结果表明 ,抑制素主动免疫能引起山羊超数排卵。 相似文献
32.
青藏高原金露梅灌丛与矮嵩草草甸枯枝落叶的分解作用 总被引:7,自引:1,他引:7
研究青藏高原金露梅灌丛和矮嵩草草甸两种植被类型枯枝落叶分解作用强度及其随着埋放时间延长的变化规律.结果表明,两种植被的枯枝落叶在埋放的前3个月均显示出明显的分解效果.其总分解率分别达到20.31%和30.4%,随后分解率逐渐降低,埋放后个月的总分解率仅为前3个月的37.60%和39.33%.矮嵩草草甸枯枝落叶的分解率显著高于金露梅灌丛.土壤温度、微生物数量和枯枝落叶本身的化学成分是影响分解率的主要因素.与其相比,动物粪便的分解率很低. 相似文献
33.
Hygienic and ecological risks connected with utilization of animal manures and biosolids in agriculture 总被引:2,自引:0,他引:2
In recent years the fate of human and animal pathogen microorganisms as a potential pollutant of the environment has been paid increased attention. Substantial quantities of these compounds and their metabolites are excreted, flushed down the drain, discarded as waste, or left over in animal feedlots. After passing to the sewer, several of these compounds are not adequately eliminated by the methods that are currently used in sewage treatment. Substantial quantities of biosolids and livestock manure end up on agricultural land. Effective sanitation of the environment, particularly of some of its special parts, which can be a source of spreading of diseases, plays an important role in prevention of infectious diseases. In this respect special attention should be paid to the disinfection of infected farm animal excrements. Sanitation of excrements should, on the one hand, ensure effective inhibition of infectious agents and, on the other hand, comply with the requirement of preserving the composition of the manure so it can be used in agricultural production. 相似文献
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Malcolm P. Caulfield Heather Cambridge Susan F. Foster Paul D. McGreevy 《Veterinary journal (London, England : 1997)》2014,199(2):223-228
Recent investigations by the Australian Department of Agriculture, Fisheries and Forestry into high mortalities on live export voyages from Australia to the Middle East during the Northern hemisphere summer suggest that animal welfare may be compromised by heat stress. The live export industry has generated a computer model that aims to assess the risk of heat stress and to contain mortality levels on live export ships below certain arbitrary limits. Although the model must be complied with under Australian law, it is not currently available for independent scientific scrutiny, and there is concern that model and the mandated space allowances are inadequate. This review appraises the relevant literature on heat stress in sheep and cattle, including laboratory studies aimed at mimicking the ambient temperatures and humidity levels likely to be encountered on live export voyages. Animal welfare is likely to be very poor as a result of heat stress in some shipments. 相似文献
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Syndromic surveillance systems can enhance early disease warning, endemic disease monitoring, or help to accumulate proof of disease freedom. In order to provide immediate feedback to achieve these goals, the health data sources scanned should be acquired continuously, in an automated fashion, and should be stored electronically. Recognizing that data from diagnostic test requests often meet these requirements, two systems designed to automatically extract surveillance information from animal laboratory databases have been developed and are described in this paper. These systems are designed to contribute to early disease detection, as well as the timely management of epidemiological information, in a province of Canada and in Sweden, the areas served by the diagnostic laboratories concerned. Classifying in-coming requests into syndromes, the first step, was the most time-consuming and the least portable step between the two systems. The remaining steps were more easily adjusted from one system to implementation in the other. These steps included: retrospective evaluation of data to create baseline profiles following the removal of excessive noise and aberrations; the identification of temporal effects; prospective evaluation of detection algorithms; and finally real-time monitoring and implementation. Building upon the institutions’ existing data management software, all steps to use those data for the purposes of syndromic surveillance were set up using open source software; as a result this approach could be readily adopted by other institutions. Relatively straight-forward development and maintenance is expected to lead to the incorporation of these systems into each institution's surveillance processes, becoming an indispensable tool for diagnosticians and epidemiologists, as well as stimulating further technical development of such systems. 相似文献
40.
二丁酰环腺苷酸对猪胴体组成和肉品质的影响 总被引:1,自引:0,他引:1
通过皮下注射和饲料添加不同剂量dbcAMP进行饲养试验 ,研究其对肥育猪胴体组成和肉品质的影响。结果表明 :皮下注射 1.0mg/kg和饲料添加 2 0mg/kg对改善肥育猪的胴体组成和肉品质效果最好 ,眼肌面积分别提高31.99%和 36 .39% (P <0 .0 5 ) ;瘦肉率分别提高 12 .4 2 %和 11.94 % (P <0 .0 5 ) ;背膘厚分别降低 19.95 %和 2 0 .97%(P <0 .0 5 )。肌肉粗蛋白含量分别提高 10 .87%和 16 .5 4 % (P <0 .0 5 )。 相似文献