共查询到20条相似文献,搜索用时 296 毫秒
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本文针对中国奶牛产业资源不足,奶牛繁育技术落后之现状,提出善用海外资源,利用胚胎生产技术的选择战略,加速中国奶牛产业的发展建议。重点介绍了现行繁育技术的缺点、体外胚胎生产、超排卵及胚胎移植技术、胚胎生产的优势及前景展望。 相似文献
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本文主要从胚胎移植技术的发展,胚胎移植技术在奶牛生产、育种生产、保种生产中的应用和胚胎移植的意义等方面介绍胚胎移植技术在畜牧业生产中的应用,并对其发展及前景进行了阐述。 相似文献
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丁酸钠作为一种新型的绿色饲料添加剂,被广泛应用于断奶仔猪及母猪生产中。本文主要综述了丁酸钠在断奶仔猪及母猪生产中的应用研究进展,以期为养殖户和兽医技术工作者提供理论技术参考。 相似文献
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根据四川省西充蚕种场及原蚕片区省力化技术的应用情况,简要分析了蚕种生产省力技术推广现状和面临的问题,提出蚕种生产省力化技术的发展对策。 相似文献
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《Preventive veterinary medicine》1988,6(3):171-181
Computer simulation was carried out to determine the optimal combination of sampling plan and sample size for estimation of four health and production variables in California Dairy Herd Improvement Association (DHIA), member herds. Three sampling plans i.e. simple random, stratified (by herd size) random with proportional allocation and stratified random with Neyman allocation, called hereafter Sampling plans 1,2 and 3, respectively, and 8 levels of sample size (10–80, in increments of 10 herds) were used to estimate parameters of 4 production and health variables: average milk production, California Mastitis Test (CMT) score, average days open and services per conception. The sampling frame used was the list of California DHIA member dairy herds in June 1984. Simulation involved generating 1000 random samples for each comparison variable for the 24 combinations of sampling plan and sample size. Three bounds on the error of estimation (5,10 and 20%) of the 4 comparison variables were specified to compute the frequency of sample means falling within these bounds for each strategy.Based on the frequency criterion, no difference was found between Sampling plans 1 and 2 for all comparison variables except average milk production. For average milk production with a 5% bound on the error of estimation, Sampling plan 2 gave more precise estimates than Sampling plan 1 for sample sizes of 40–70. However, this difference did not exist using either a 10 or 20% bound on the error of estimation. For average milk production, Sampling plan 3 yielded a substantially larger percentage of point estimates within a 5 or 10% bound on the error for all sample sizes considered than Sampling plans 1 and 2. Similar results were observed for CMT score using sample sizes between 30 and 80 dairy herds. For average days open, Sampling plan 3, relative to Sampling plan 1 and 2, yielded 4–8% more point estimates of population parameter within a 5% bound on the error of estimation with sample sizes of 40–80. No meaningful difference was noticed among the three sampling plans for estimation of mean services per conception.Sampling plan 3 was the most efficient sampling plan for the health and production variables considered in this study. With respect to sample size, the mean of such production variables as average milk production, services per conception and average days open could be estimated with precision using a sample size of 80 or less dairy herds. For disease variables with variance structure similar to CMT score, precise estimates cannot be obtained using sample sizes of up to 80 herds; a sample size substantially larger than 80 herds would be required to provide a precise estimate of the central value. 相似文献
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本文人淳安县蚕桑的现状及存在问题分析中,提出今后蚕桑中持续发展的途径与措施。包括规划、政策、投入、技术等措施。 相似文献
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重庆市"十五"肉牛生产的现状与"十一五"发展对策 总被引:1,自引:0,他引:1
重庆市肉牛生产在“十五”期间取得很大的发展,尤其是在肉牛的生产科研中取得重庆市肉牛生产在“十五”期间取得很大的发展,尤其是在肉牛的生产科研中取得了较好的成绩。本文阐述了重庆市现有的肉牛资源条件、生产水平、市场因素等现状,指出了重庆市肉牛生产中存在的问题,并对重庆市“十一五”期间肉牛生产搞好资源的综合利用,实现可持续发展的对策进行了探讨。 相似文献
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生物安全是猪场生产管理的关键,也是猪场搞好生产的基本保障。猪场生物安全贯穿于生产管理的各个环节,包括人员、物资、猪只、饲料、粪污等流转运输等。近两年的非洲猪瘟疫情使得很多生物安全设施和管理不健全的养殖场遭受灭顶之灾。为协助众多在疫情中遭受打击的规模养殖企业恢复生产,文章从更严格的生物安全角度出发,在传统猪场工艺设计的基础上,对猪场功能区设置、人员物料流线规划、进出场洗消设施配置等提出了一套较为完整的工艺技术方案,供养猪从业者在新建和改造猪场复养过程中参考。 相似文献
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加强科技创新,促进我国肉牛种业建设 总被引:1,自引:0,他引:1
在全面分析我国肉牛产业发展的基础上,针对当前肉牛种业面临的品种选育缺乏科学规划、良种繁育体系不健全、良种良法不配套、国民食物结构有待改善以及牛肉供应不足等问题,提出了设立育种专项,加强肉牛生物技术研究和应用项目、育种资金投入、强化育种组织建设、推动产学研实质融合解决方案. 相似文献
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Dairy Comp 305 program 总被引:1,自引:0,他引:1
W Goodger 《Veterinary Clinics of North America: Food Animal Practice》1987,3(3):553-559
A flexible dairy database program, Dairy Comp 305, is described to illustrate how a dairy database can support the decisions of a dairy producer and provide data for veterinarians to plan their production management programs. 相似文献