Research Center of Animal Production, University of Lleida, Lleida, Spain.
Theriogenology. 2012 Apr 1;77(6):1029-41. doi: 10.1016/j.theriogenology.2011.10.014. Epub 2011 Dec 6.
After 80 years of the commercial application of artificial insemination (AI) in the cow, the method still has numerous benefits over natural insemination including worldwide gene improvement. The efficiency of insemination depends, among many other factors, on the delivery of an appropriate number of normal spermatozoa to the appropriate reproductive tract site at the appropriate time of estrus. The metabolic clearance of steroid hormones and pregnancy associated glycoproteins and the negative effects of different types of stress related to high milk production makes the high-producing dairy cow a good animal model for addressing factors affecting fertility. Nevertheless, extensive studies have shown a positive link between high milk production in an individual cow and high fertility. When a cow becomes pregnant, the effect of pregnancy loss on its reproductive cycle is also a topic of interest. This paper reviews the factors of a noninfectious nature that affect the fertility of lactating dairy cows following AI. Special attention is paid to factors related to the cow and its environment and to estrus confirmation at insemination. Pregnancy maintenance during the late embryonic/early fetal period is discussed as a critical step. Finally, the use of Doppler ultrasonography is described as an available research tool for improving our current understanding of the health of the genital structures and conceptus.
人工授精（AI）在奶牛中的商业应用已经有 80 年了，该方法仍然具有许多优于自然授精的优势，包括全球基因改良。授精效率取决于许多因素，包括在发情期适时将适当数量的正常精子输送到适当的生殖道部位。甾体激素和妊娠相关糖蛋白的代谢清除以及与高牛奶产量相关的不同类型的应激的负面影响使得高产奶牛成为研究影响生育力的因素的良好动物模型。然而，广泛的研究表明，个体奶牛的高牛奶产量与高生育力之间存在正相关。当奶牛怀孕时，怀孕损失对其生殖周期的影响也是一个关注的话题。本文综述了非传染性因素对人工授精后泌乳奶牛生育力的影响。特别关注与奶牛及其环境有关的因素，以及授精时的发情确认。胚胎/早期胎儿后期的妊娠维持被讨论为一个关键步骤。最后，描述了使用多普勒超声作为一种可用的研究工具，以提高我们对生殖结构和胚胎健康的现有理解。
