后备母牛的饲养管理appt课件.ppt

  1. 1、本文档共122页,可阅读全部内容。
  2. 2、有哪些信誉好的足球投注网站(book118)网站文档一经付费(服务费),不意味着购买了该文档的版权,仅供个人/单位学习、研究之用,不得用于商业用途,未经授权,严禁复制、发行、汇编、翻译或者网络传播等,侵权必究。
  3. 3、本站所有内容均由合作方或网友上传,本站不对文档的完整性、权威性及其观点立场正确性做任何保证或承诺!文档内容仅供研究参考,付费前请自行鉴别。如您付费,意味着您自己接受本站规则且自行承担风险,本站不退款、不进行额外附加服务;查看《如何避免下载的几个坑》。如果您已付费下载过本站文档,您可以点击 这里二次下载
  4. 4、如文档侵犯商业秘密、侵犯著作权、侵犯人身权等,请点击“版权申诉”(推荐),也可以打举报电话:400-050-0827(电话支持时间:9:00-18:30)。
查看更多
后备母牛的饲养管理appt课件

* Fewer papillae per unit area reflects bigger papillae with greater nutrient absorption capacity. Hence, with 2% XP the rumen was much more developed and capable of digesting complex carbohydrates and absorbing VFAs. An underdeveloped rumen may restrict calf growth for two to four weeks after weaning, adversely affecting time of breeding and subsequent age at first calving. * * The absorption of the fermentation end-products is an important criterion of ruminal development. In mature animals, VFA’s and other fermentation end-products are absorbed into the rumen epithelium where propionate and butyrate are metabolized. Then, the VFA’s or end products of metabolism (lactate and β-hydroxybutyrate) are transported to the liver for use as energy substrates. In neonatal calves there is little or no absorption or metabolism of VFA’s. Hence, the rumen must develop this ability prior to weaning. * * The rumen wall consists of epithelial and muscular layers. The muscular layer provides support for the interior (epithelial layer) and moves ruminal contents in the rumen. The epithelial layer is the absorptive layer containing many fingerlike projections called papillae. The papillae provide the absorptive surface for the rumen. At birth, the papillae are small and non-functional. They absorb little and do not metabolize significant VFA’s. The primary stimulus for papillae development are the VFA’s – particularly propionate and butyrate. Rumen development is driven by the availability of dry feed, especially the starter grain in the rumen. Calves should be offered a grain based starter ration and fresh, clean water, in addition to milk after their first day of life. * * * * * * * * * * * * * 发育牛/育成牛 1、饲 养 2、管 理 3、易出现的问题及解决措施 发 育 牛 特点: 生长发育最旺盛时期,疾病少,容易 管理。 要充分利用牛自身的“生长发育旺盛”的生理特点,除了能获得高的增重外,还要获得完美的内在器官发育及适应环境的能力。 繁育机能发育变化 荷斯坦牛的性成熟年龄大约在6-14月龄。生殖器重量的增加(♀)在6个月龄以前与体重增加是平行进行,其后发育超过体发育。10个月龄后变慢,荷斯坦牛的初情期约在10个月龄、体重250千克、体高110-115cm时出现。 乳腺发育 若实行高营养

您可能关注的文档

文档评论(0)

wuyoujun92 + 关注
实名认证
内容提供者

该用户很懒,什么也没介绍

1亿VIP精品文档

相关文档