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如何保证DHI测试数据的准确性 总被引：1，自引：1，他引：0
DHI报告可以为牧场饲养管理提供决策依据,为育种工作提供完整而准确的资料,前提是必须保证数据的准确,从而指导正确的决策,达到事半功倍的效果. 相似文献
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我国开展奶牛生产性能测定工作20多年来取得了一些进步,各地DHI工作也在有序开展。本文具体阐述了上海市的DHI应用情况,并通过此例对我国DHI工作中存在的问题和误区进行分析。DHI分析报告是牧场生产管理的科学依据,牧场管理者应结合牧场的生产状况,正确使用报告中的数据,科学管理奶牛,使奶牛生产走向健康、可持续的发展道路。 相似文献
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提高高峰产奶量的重要性 总被引：1，自引：0，他引：1
DHI测试系统(奶牛生产性能测定)是奶牛育种的基础工作,同时它为奶牛场生产提供先进科学的管理手段。在DHI报告中已知乳体细胞数水平直接反映奶牛乳腺的感染情况,从而懂得了控制体细胞数对增产的重要性;DHI又为我们提供了估计305天产量,从而提高生产管理者对个体牛或全场牛单产的预见性;奶产量和乳成分又是最直观反映着奶牛营养水平,所有的DHI测试记录都是为提高牧场管理水平所服务的,而其中很重要的一个指标就是高峰产奶量(Peak Milk),高峰产奶量是指整个泌乳期中奶量最高的日单产,高峰产奶量可直接影响到整个胎次的产量,如果奶牛场希望自己的产量是10000kg而不是5000kg,那么必须管理好高峰产奶量,尽量提高奶牛的高峰产奶量。 在中加奶牛育种综合项目的帮助下,上海建立了DHI测 相似文献
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以云南省昆明市某牧场2018年1—12月的奶牛生产性能测定（DHI）数据为基础,统计平均胎次、泌乳天数、305 天产奶量、体细胞数、乳脂率、乳蛋白率、产奶高峰日、高峰奶量等指标,将其与DHI指标标准范围进行比较,分析、查找存在的问题。结果显示,该牧场平均胎次为2.43,泌乳天数为166 天,305 天产奶量为9 169 kg,体细胞数为24 万个/mL,乳脂率为3.78%,乳蛋白率为3.27%,高峰奶量为40.3 kg,产奶高峰日在73.2 天。结果表明,该牧场的牛群结构相对合理,配种繁殖性能正常,但存在隐性乳房炎,高峰日过长等问题。建议应该加强育成牛、干奶期、围产期奶牛的饲养管理,降低乳房炎发生率,缩短高峰日时间。 相似文献
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DHI-牧场管理的有效工具 总被引：6，自引：0，他引：6
DHI(Dairy Herd Impmvement,奶牛群改良)奶牛性能测定体系,是通过测试奶牛的奶产量、乳成分(乳脂、乳蛋白等)、体细胞数并收集牛群有关资料,经分析后形成反映牧场配种、繁殖、饲养、疾病、生产性能等信息检测报告。通过这些信息可以科学高效地指导牧场生产管理。 相似文献
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本文收集广东省某一DHI参测规模化奶牛场2021年1-12月份的测定数据及牛群的基础资料，运用CNDHI和Excel软件对该场全年乳脂率、乳蛋白率、脂蛋比、乳尿素氮、体细胞数、胎次及泌乳天数指标进行综合分析。结果表明，该场2021年乳脂率、脂蛋比、乳尿素氮指标整体偏低；SCC>50万/mL的牛数有下降趋势；而头胎奶牛及泌乳天数在200d以上牛数占比偏高。由此可见，奶牛场正确解读DHI报告并将其应用于牧场生产有利于及早发现牧场生产中存在的问题，还可以及时改善该牧场日粮结构、环境卫生、牛群结构以及繁殖状况等方面存在的问题，提高牧场生产管理水平及经济效益。 相似文献
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DHI牛奶测定技术在奶牛生产中的作用 总被引：3，自引：0，他引：3
DHI牛奶测定技术在我国经过近十年的推广实施已具一定的规模和影响 ,可应用于奶牛乳房健康管理、奶牛饲料营养调整、选种选配、牧场的日常管理等。1 DHI牛奶测定技术的概念与意义DHI(Dairy Herd Improvement牛群改良 )牛奶测定技术是奶牛饲养的核心技术。旨在加强牧场的管理基础和遗传基础 ,提高奶牛生产的产量、质量和效率。主要通过每月一次对泌乳牛的牛奶测试 (测试牛奶脂肪、蛋白、乳糖和体细胞数 ) ,记录牛只基础资料 ,运用先进的牛群管理软件形成数据化的信息报告 ,最后以这些信息报告来指导生产和管理。2 DHI牛奶测定技术… 相似文献
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魏静 《四川畜牧兽医学院学报》2009,(4):28-32
在现代法律秩序中,商会自治规范是制定法的基础和必要的补充,甚至在某些方面替代了制定法;商会自治规范主要包括商会组织规范、行为规范、惩罚规范以及争端解决规范等;其效力仅及于其内部成员;商会自治规范和制定法之间存在冲突,但也存在整合的基础。 相似文献
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本文概述了猪的毛色类型、猪的毛色遗传模式,着重综述了猪毛色基因分子基础的研究进展,指出存在问题并就未来发展方向做了思考。 相似文献
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以国际标准强毒Ｒ株人工感染非免疫产蛋鸡,定时扑杀,分别从鼻窦、眶下孔、气管、肺、气囊、卵巢和输卵管分离ＭＧ,并收集感染鸡所产蛋分离ＭＧ。结果表明,人工感染４８小时后上、下呼吸道及肺已被全面感染,９６小时气囊已被感染,１２０小时输卵管已能分离到ＭＧ,卵巢始终分离不到ＭＧ。人工感染鸡自１４４小时便能在其所产蛋中分离出ＭＧ。药物治疗能在７２小时内消除感染,油乳剂苗则需２４天后逐渐降低蛋内ＭＧ分离率,药物卵内注射、种蛋药浴、高温处理均能杀死卵内ＭＧ,但以研制的种蛋浸泡剂药浴效果为最好。 相似文献
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REASONS FOR PERFORMING STUDY: Centesis of the bicipital bursa using an 8.9 cm long spinal needle has been reported but the alternative of employing a 3.8 cm long hypodermic needle requires validation. OBJECTIVE: To compare the efficacy of 2 different methods of centesis of the bicipital bursa and to evaluate the usefulness of ultrasonographic imaging to determine the location of solution administered when centesis of the bursa is attempted. METHODS: For Trial 1, 6 clinicians, who had no previous experience of centesis of the bicipital bursa, attempted to inject a solution composed of an aqueous radiopaque contrast medium and physiological saline solution (PSS) into the bicipital bursae of 2/12 horses using the previously described distal approach to inject one bursa and a proximal approach to inject the contralateral bursa. The bicipital tendon and bursa were examined ultrasonographically before and after injection; and both shoulders were examined radiographically to identify the location of the medium. In Trial 2, another 6 clinicians, also with no previous experience of centesis, repeated Trial 1, using 6 horses, but the radiopaque contrast medium was mixed with air instead of PSS. RESULTS: Accuracy of centesis using the proximal approach was 39% and that of the distal approach 28%. Ultrasonographic examination of the shoulder allowed the location of solution and air to be accurately predicted in all 12 shoulders examined. CONCLUSIONS: Clinicians who have had no previous experience performing centesis of the bicipital bursa are unlikely to be successful in centesis using either approach. Radiographic examination after injecting a radiopaque contrast medium may be necessary to assess the success of centesis especially if bursal fluid is not obtained during centesis. Injecting air along with the radiopaque contrast medium provides more accurate ultrasonographic confirmation of centesis and better radiographic definition than does injection without air. 相似文献
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Effects of size of ingestively masticated fragments of plant tissues on kinetics of digestion of NDF
Ingestively masticated fragments were collected and sized via sieving. Different sizes of esophageal masticate and ruminal digesta fragments, and ground fragments of larger masticated pieces were incubated in vitro, and undigested NDF remaining at intervals of up to 168 h of incubation was determined. The ruminal age-dependent time delay (tau) for onset of digestion of NDF was positively correlated (P < 0.004) with the mean sieve aperture estimated to retain 50% of the fragments between successive sieve apertures (MRA). Degradation rate of potentially degradable NDF (PDF) and level of indigestible NDF were not related (P > 0.10) to MRA of masticated and ground fragments. Estimates of tau were positively related to MRA, with slopes of bermudagrass < corn silage < ruminal fragments of corn silage. It was concluded that fragment size-, and consequently, ruminal age-dependent onset of PDF degradation of a mixture of different fragment sizes results in an age-dependent rate of degradation of the more rapidly degrading of two subentities of PDF. Models are proposed that assume a tau before onset of simultaneous degradation of PDF from two pools characterized as having gamma-modeled age-dependency and age-constant rates. The ruminal age-dependent pool seems to be associated with the faster-degrading pool, and its rate parameter increases with range in MRA in the population of fragments. Conceptually, the ruminal age-dependent rate parameter for PDF degradation seems to represent a composite of several effects: 1) effects of the size-dependent tau; 2) range in MRA of the population of ingestively masticated fragments; and 3) subentities of PDF that degrade via more rapid age-dependent rates compared with subentities of PDF that degrade via age-constant rates. The estimated fractional rates of ruminative comminution of ingestively masticated fragments (0.060 to 0.075/h) were of a magnitude similar to the mean fractional rates of PDF digestion (0.030 to 0.085/h), which implies that ruminative comminution may be first-limiting to fractional rate of PDF digestion. The in vivo roles of ingestive and ruminative mastication of fragments on PDF degradation must be considered in any kinetic system for estimating PDF digestion in the rumen. These results and others in the literature suggest that the rate of surface area exposure rather than intrinsic chemical attributes of PDF may be first-limiting to degradation rate of PDF in vivo. 相似文献