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随着十多年的超速发展,我国奶牛业已由单一品种的散养方式逐步转变为高产品种的规模化、集约化养殖方式。然而,我国奶牛整体遗传素质不高,多为进口高产奶牛与地方奶牛的低代次改良品种,以致原奶质量参差不齐,严重制约了我国奶业的健康发展。因此,大规模引进高品质的奶牛品种,已成为我国优化奶牛基因、推动畜牧业产业化发展的重要抓手,但同时也为检疫工作带来了挑战。本文通过分析2018年我国进口奶牛数量、来源国、疫病检出、进境口岸及隔离检疫场分布等数据,结合各来源国的疫病防控特点,有针对性地提出检疫要点,为我国全面提升进口奶牛的检疫水平、切实做好奶牛群体遗传改良计划、加快推进畜牧业转型升级提供参考。  相似文献   
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对中国农科院执行“948”计划的回顾与思考   总被引:1,自引:1,他引:0  
文章总结了14年来中国农业科学院执行引进国外先进农业科学技术计划(以下简称"948"计划)取得的效果,分析了"948"项目引进与引进后消化吸收再创新工作的关系,从引进原则、重点领域、立项新思路、项目策划要点等方面提出了新见解,旨在为未来"948"选题提供借鉴。  相似文献   
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Strategies designed to minimize the probability of bluetongue virus (BTV) introduction to new areas should be based on a quantitative assessment of the probability of actually establishing the virus once it is introduced. The risk of introducing a new strain of bluetongue virus into a region depends on the number of viremic animals that enter and the competency of local vectors to transmit the virus. We used Monte Carlo simulation to model the probability of introducing BTV into California, USA, and the US through importation of cattle. Records of cattle and calf imports into California and the US were obtained, as was seroprevalence information from the exporting countries. A simulation model was constructed to evaluate the probability of importing either a viremic PCR-negative animal after 14-day quarantine, a c-ELISA BTV-antibody-negative animal after 28-day quarantine, or an untested viremic animal after 100-day quarantine into California and into the US. We found that for animals imported to the US, the simulated (best to worst scenarios) median percentage that tested positive for BTV-antibody ranged from 5.4 to 7.2%, while for the subset imported to California, the simulated median percentage that tested positive for BTV-antibody ranged from 20.9 to 78.9%. Using PCR, for animals imported to the US these values were 71.8–85.3%, and for those imported to California, the simulated median that test positive ranged from 74.3 to 92.4%. The probability that an imported animal was BTV-viremic is very low regardless of the scenario selected (median probability = 0.0%). The probability of introducing an exotic strain of BTV into California or the US by importing infected cattle was remote, and the current Office International des Epizooties (OIE) recommendation of either a final PCR test performed 14 days after entry into quarantine, a c-ELISA performed 28 days after entry into quarantine or a 100-day quarantine with no testing requirement was adequate to protect cattle in the US and California from an exotic strain of BTV.  相似文献   
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常文娟 《安徽农业科学》2005,33(7):1149-1150,1155
通过分析当前棉花进口贸易中存在的问题和棉花进口贸易自由化对棉农、棉纺企业和棉商的影响,主张我国应加快推进棉花进口贸易自由化进程,并就在这一进程中如何应对自由贸易带来的冲击进行了探讨。  相似文献   
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中国木材市场现状、存在问题和发展建议   总被引:4,自引:0,他引:4  
介绍了中国木材市场供需和进口现状及发展趋势。建议发展木结构房屋和铁路杨木枕木等以人工林为主要原料的木材制品,改变消费观念,促进人造板工业发展,调整人造板消费结构,扩大在建筑方面的应用,以木材工业的发展促进林业的发展。提出扩大非公有制人工林发展,大力进口俄罗斯木材和新西兰木材,以弥补国产木材不足。并建议适当减少热带阔叶木材进口,以保护全球生态环境。  相似文献   
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AIMS: To quantify the numbers of live cattle, sheep and poultry imported into New Zealand and, where possible, their country of origin from 1860 to 1979.

METHODS: Information on the origin and number of live animal importations into New Zealand was collected for cattle, sheep and poultry for the period 1868–1979 from the annual reports compiled by the New Zealand Registrar General's Office, Government Statistician's Office, Census and Statistics Office, Census and Statistics Department, Customs Department and Department of Statistics. Census data from 1851 to 1871 were also used to estimate the livestock population during this period. The number of animals imported and the mean population for each species in a decade were determined, and the major countries of origin were identified.

RESULTS: A large number of cattle (53,384) and sheep (604,525) were imported in the 1860s, and then there was a marked reduction in importations. Live poultry were imported in relatively small numbers (20,701) from 1880 to 1939, then 1,564,330 live poultry were imported between 1960 and 1979. Australia was the predominant country of origin for sheep between 1868 and 1959 (51,347/60,918; 84.3%) and of cattle between 1868 and 1979 (10,080/15,157; 66.5%). Only 6,712 (11.0%) sheep and 3,909 (25.8%) cattle were imported from the United Kingdom over the same periods, and even fewer from other countries.

CONCLUSIONS: The collated data and historical reports show that from 1860 to 1979 Australia has been the main source of livestock introduced into New Zealand. The pattern of importation showed that large numbers of cattle and sheep were initially imported in the 1860s, probably in response to rapid agricultural expansion. Thereafter importations continued at much reduced numbers. In contrast, relatively small numbers of poultry were introduced until the 1960s when large numbers were imported as part of the development of a modern high-production industry. The overall pattern for both cattle and sheep was of a bottleneck event, as initially a relatively limited number of animals arrived from outside populations, followed by population expansion with ongoing but limited immigration (admixture). Investigation into the genetic population structure of New Zealand's cattle and sheep, as well as their host-associated microorganisms, could reflect the impact of these early historical events.  相似文献   
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