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首页> 外文期刊>Irish Veterinary Journal >Reproductive management of dairy cows: A review (part I)
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Reproductive management of dairy cows: A review (part I)

机译：奶牛的生殖管理：回顾（第一部分）

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In the first of two articles on the the role of management factors in herd reproductive performance, the importance of early resumption of ovuiatson and excellent oestrous detection efficiency are reviewed. Reproductive efficiency is a major factor affecting production and economic efficiency in dairy herds. In seasonally calving herds, the requirement of good reproductive performance is of greater importance than in other production systems in order to maximally exploit the use of grazed grass in the diet of the cow. Reproductive performance of lactating dairy cows worldwide has declined over the past 30 years in association with selection for milk yield. There is increasing and consistent evidence to suggest' that at least some part of the declinein cow reproductive performance is related to underlying changes in reproductive physiology caused by high milk production and or negative energy balance in early lactation. In a recent review, Wiltbank et al. (2006) reported that the duration of oestrus and conception rates were both lower in lactating cows compared to heifers, while the incidence of twinning and late embryo loss were higher in lactating cows. In this two-part article, the role of management factors in herd reproductive performance, particularly in cows managed for seasonal calving, will be reviewed. While there are numerous factors that affect the reproductive performance of individual cows, and consequently herd reproductive performance, they can be categorised under the followingthree broad headings: (i) the interval from calving to resumption of ovulation and regular oestrous cycles; (ii) oestrous detection efficiency and submission rate; and (iii) conception rate following service.
机译：在有关管理因素在畜群繁殖性能中的作用的两篇文章的第一篇中，回顾了尽早恢复卵巢和重要的雌激素检测效率的重要性。繁殖效率是影响奶牛场生产和经济效率的主要因素。与其他生产系统相比，在季节性犊牛群中，对繁殖性能的要求比其他生产系统更为重要，以便最大程度地在母牛的饲料中利用放牧的草。在过去的30年中，随着牛奶产量的选择，全世界泌乳奶牛的生殖性能下降。越来越多的一致证据表明，“奶牛生殖性能下降的至少一部分与高产奶量或早期泌乳期能量平衡失调引起的生殖生理的根本变化有关。在最近的评论中，Wiltbank等。 （2006年）报道，与母牛相比，泌乳母牛的发情持续时间和受孕率均较低，而泌乳母牛的孪生和后期胚胎丢失率更高。在这篇由两部分组成的文章中，将回顾管理因素在畜群繁殖性能中的作用，特别是在季节性产犊的母牛中。虽然有许多因素会影响个体母牛的生殖能力，进而影响牛群的生殖能力，但可以将它们归类为以下三个大类：（i）从产犊到恢复​​排卵的间隔和正常的发情周期; （ii）极好的检测效率和提交率; （iii）服务后的受孕率。

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