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排序方式: 共有657条查询结果,搜索用时 15 毫秒
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K. Forde A. Hillberg-Seitzinger D. Dargatz N. Wineland 《Preventive veterinary medicine》1998,37(1-4):209-217
Knowledge about the patterns of animal movement – particularly feeder-cattle movement – within the USA is necessary in order to anticipate how diseases might be spread geographically. This study was conducted to explore the availability of interstate-level movement data which might be used to develop a more coherent national picture of interstate feeder-cattle movement. State Statistical Offices of the National Agricultural Statistics Service, 1996 (NASS) and Departments of Agriculture in all 50 states were contacted to determine the type of information collected regarding the import and export of feeder cattle. Eighteen of the 50 states contacted recorded updated import and export information by using certificates of veterinary inspection and (occasionally) entry permits for verification. The 18 states were: Alabama, Colorado, Florida, Hawaii, Idaho, Illinois, Indiana, Iowa, Kansas, Maryland, Massachusetts, Minnesota, New Jersey, Pennsylvania, Texas, West Virginia, Wisconsin, and Wyoming. Profiles of import and export data from Kansas, Texas, Colorado and Iowa (the primary receivers of 51% of total 1995 imports) were developed. These four states received at least 50% of their cattle imports from <9 different states. As a result, approximately half of the nation's import movement can be explained by a total of 13 states and Mexico (excluding duplicates). Also, >50% of the exports from Kansas, Texas, Colorado, and Iowa go to ≤3 states. This import and export information confirms conclusions of others that cattle tend to move toward the center of the USA. However, if more states kept comprehensive, up-to-date records of movement information, knowledge about cattle-movement patterns in the USA would be importantly increased. The lack of specific notations on certificates of veterinary inspection can lead only to perceived trends; the present records have limited value in tracking animal movement. 相似文献
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H. Korkeala T. Alanko O. Mtiki-Pettiys O. Sorvettula 《Acta veterinaria Scandinavica》1988,29(1):15-22
The effect of the pH on the boiling test was studied in 68 beef and 108 pork muscles. The pH had a significant effect on the sensory scores obtained from the boiling test. The effect was particularly pronounced in the odour of meat. In beef the odour scores remain steady for samples with a pH value under about 6.2 and start to increase rapidly in higher pH values. In pork the increase in scores appears to be linear. The odour observed in high pH meat was described by the judges as abnormal and ammonialike. In the case of meat with a high pH, the results of the boiling test at meat inspection should be interpreted with extreme caution. 相似文献
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Ngowi HA Kassuku AA Maeda GE Boa ME Willingham AL 《Tropical animal health and production》2004,36(4):335-340
A survey on extra-intestinal porcine helminths was conducted at three slaughter slabs that receive pigs from Mbulu, a district endemic for porcine cysticercosis in northern Tanzania. Seventy carcases of pigs between 1 and 2 years old were examined between December 1997 and March 1998. The examination involved ante-mortem lingual examination for Taenia solium cysticercosis followed by post-mortem inspection. In addition, a laboratory procedure was performed to determine whether any of these domestic pigs were infected with Trichinella species. Parasites detected were Ascaris suum (44.3%), Echinococcus granulosus (4.3%) and Taenia hydatigena (1.4%). The lack of cases of porcine cysticercosis in this study compared to previous studies suggests that pig traders are conducting their own ante-mortem lingual examinations before purchasing pigs in the rural communities where the parasite is still highly prevalent. It is concluded that improved meat inspection could prove useful in reducing the local population's risk of infection with these parasites. The results of this study have revealed the parasites of agricultral and public health importance in the targeted communities. Further epidemiological investigations are required to better determine parasite prevalence and impact in order to formulate appropriate and cost-effective strategies for control. 相似文献
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加固回填地基的方法主要有分层回填碾压、桩基和强夯加固3种方法。而强夯加固法是一种适用范围较广的地基处理方法,具有效果显著、施工方便、节材省时等优点。其主要技术指标是影响深度、单击夯击能、夯击次数、夯击遍数及夯点间距。以秦皇岛首站5号10×10~4m~3油罐深层回填地基处理实践为例,着重介绍了运用强夯加固法回填地基的处理方法,根据初步确定的强夯参数,提出强夯试验方案,在具有代表性的场地中选取一个或几个试验区,进行现场试夯,再根据不同土质条件,待试夯结束一至数周后,对试夯区进行测试,并与夯前测试数据进行对比,用以检验强夯效果、确定工程采用的各项强夯参数。强调了在强夯施工中应注意的事项。 相似文献
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草种子不仅是草业与畜牧业的基石,还是生态文明建设以及城镇景观绿化的重要载体。我国虽是草地资源和草种子利用大国,但却是草种业弱国。标准化是推动草种业快速高质量发展的关键,历经30多年的不懈努力,我国的草种业标准化也取得了积极的进展,但是目前的草种业标准体系还处于混沌状态,缺乏系统的梳理。为了进一步加强和完善我国草种业标准体系构建,推动草种业高质量发展,本文尽可能详细地检索和筛选草种业的现行标准,从种质资源、生产加工、质量检验、包装、贮藏和运输,播种5个方面进行梳理。在此基础上分析了现行标准体系的薄弱之处,提出了需要更新以及尚需制定标准的建议,为草种业标准的制定者和应用者提供服务和便利,为草种业标准体系的完善提供参考。 相似文献
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