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通过生存分析评估的南非非洲牛的寿命
Allison M Bot Steffl1, Michael D MacNeil2,3,4, Michiel M Scholtz3,4
1Department of Animal Science, South Dakota State University, Brookings, South Dakota, USA.
概括
非洲人牛的生产寿命不到六年,年轻的第一次母亲的寿命更长. 遗传选择可以提高这种坚固的南非品种的生产寿命.
科学领域:
- 动物科学动物科学
- 兽医医学 兽医医学 兽医医学
- 农业经济学 农业经济学
背景情况:
- 南非本土的非洲人牛品种以其性而闻名.
- 从历史上看,在南非农民中最受欢迎的品种,Afrikaner牛的数量最近有所下降.
研究的目的:
- 评估影响非洲牛生产寿命的因素.
- 将生产寿命定义为第一个和最后一个产生的小牛之间的间隔.
主要方法:
- 用生存分析来分析40年来374个群体中29379头非洲牛的数据.
- 这项研究研究了第一次分娩和出生季节的年龄对生产生活的影响.
- 对生产生活的遗传参数,包括遗传性,进行了估计.
主要成果:
- 非洲人牛的生产寿命中位数略低于6年.
- 奶牛在年轻时分娩,其生产寿命远远长于年长的第一次产妇.
- 12月至2月出生的奶牛的生产寿命比3月至11月出生的奶牛要短.
- 生产性生命的遗传率估计为0.225,表明显著的附加遗传变异.
结论:
- 第一次分娩的年龄和出生季节是影响非洲人牛生产生活的关键因素.
- 在非洲人品种中存在足够的附加基因变异,以促进更长的生产寿命的基因改进.
- 这些发现可以为提高非洲牛长寿和经济可行性的育种策略提供信息.
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