Fertility in high-producing dairy cows: reasons for decline and corrective strategies for sustainable improvement.
Fertility in high-producing dairy cows: reasons for decline and corrective strategies for sustainable improvement.
复制标题
高产奶牛的繁殖力：下降的原因和可持续改进的纠正策略。
DOI：
10.5661/rdr-vi-237
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发表时间：
2007
期刊：
影响因子：
--
通讯作者：
M. Lucy
中科院分区：
文献类型：
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作者：
M. Lucy
世界范围内奶牛的繁殖力下降，考虑到良好的繁殖力对乳制品行业的重要性，这种变化令人惊讶。生育率下降可以通过乳制品行业内的管理变化以及牛奶产量和繁殖之间的负遗传相关性来解释。抑制泌乳奶牛生育能力的四种主要机制是无排卵和行为性不发情（无法周期和显示发情）、次优和不规则的发情周期（此类包括卵巢疾病和配种后黄体功能不正常）、植入前胚胎发育异常（可能继发于卵母细胞质量差）和子宫/胎盘功能不全。提高高产奶牛繁殖力的解决方案将包括短期和长期组成部分。从短期来看，使用高生育力种公牛并实施受控育种计划将会有所帮助。受控育种计划可提高封闭式奶牛群的繁殖效率，并可与授精后处理相结合以提高生育力。另一种直接的短期解决方案包括改变饮食，使饮食成分引发有利于奶牛繁殖的激素反应。上述短期解决方案并没有解决纠正高产奶牛繁殖的潜在遗传学的基本需求。杂交可能会提高繁殖性能，因为它可以减少近亲繁殖，并降低具有极高产奶量表型的奶牛的产量。然而，当通过平衡的遗传选择策略改善奶牛繁殖的遗传学时，当前奶牛繁殖的危机将得到永久解决。
The fertility of dairy cows has declined worldwide and this change is surprising given the importance of good fertility to the dairy industry. The decline in fertility can be explained by management changes within the dairy industry and also negative genetic correlations between milk production and reproduction. Four primary mechanisms that depress fertility in lactating cows are anovulatory and behavioral anestrus (failure to cycle and display estrus), suboptimal and irregular estrous cyclicity (this category includes ovarian disease and subnormal luteal function after breeding), abnormal preimplantation embryo development (may be secondary to poor oocyte quality), and uterine/placental incompetence. The solution for improving fertility in high-producing dairy cows will include both short-term and long-terms components. For the immediate short-term, using high fertility sires and implementing controlled breeding programs will help. Controlled breeding programs improve reproductive efficiency in confinement-style dairy herds and can be combined with post-insemination treatments to enhance fertility. An additional immediate short-term solution involves changing the diet so that dietary ingredients invoke hormonal responses that benefit the reproduction of the cow. The short-term solutions described above do not address the fundamental need for correcting the underlying genetics for reproduction in high-producing dairy cows. Crossbreeding will improve reproductive performance perhaps because it alleviates inbreeding and also lowers production in cows with an extreme high milk production phenotype. The current crisis in dairy reproduction will be permanently solved, however, when the genetics for dairy reproduction are improved through a balanced genetic selection strategy.