Reproductive efficiency is closely tied to the profitability of dairy herds, and therefore successful dairy operations seek to achieve high 21-day pregnancy rates in order to reduce the calving interval and days in milk of the herd. There are various factors that impact reproductive performance, including the specific reproductive management program, body condition score loss and nutritional management, genetics of the cows, and the cow comfort provided by the facilities and management programs. To achieve high 21-day pregnancy rates, the service rate and pregnancy per artificial insemination (P/AI) should be increased. Currently, there are adjustments in timed artificial insemination (TAI) protocols and use of presynchronization programs that can increase P/AI, even to the point that fertility is higher with some TAI programs as compared with AI after standing estrus. Implementation of a systematic reproductive management program that utilizes efficient TAI programs with optimized management strategies can produce high reproductive indexes combined with healthy cows having high milk production termed “the high fertility cycle”. The scientific results that underlie these concepts are presented in this manuscript along with how these ideas can be practically implemented to improve reproductive efficiency on commercial dairy operations.

中文翻译：

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以定时人工授精计划为重点的优化乳牛群繁殖效率的因素

繁殖效率与奶牛群的获利能力紧密相关，因此，成功的奶牛场寻求实现21天较高的怀孕率，以减少产犊间隔和产奶天数。影响生殖性能的因素有很多，包括特定的生殖管理程序，身体状况评分下降和营养管理，奶牛的遗传学以及设施和管理程序提供的奶牛舒适度。为了达到21天的高怀孕率，应该提高服务率和每次人工授精（P / AI）的怀孕率。目前，对定时人工授精（TAI）协议和预同步程序的使用进行了调整，可以增加P / AI，甚至在某些TAI计划中，生育率要比发情后的AI高。实施系统的生殖管理计划，利用有效的TAI计划和优化的管理策略，可以产生高繁殖指数，并与被称为“高生育力周期”的高产奶量的健康奶牛相结合。这些概念背后的科学成果以及如何切实实施这些思想以提高商业乳业生产效率的方法均在本手稿中进行了介绍。实施系统的生殖管理计划，利用有效的TAI计划和优化的管理策略，可以产生高繁殖指数，并与被称为“高生育力周期”的高产奶量的健康奶牛相结合。这些概念背后的科学成果以及如何切实实施这些思想以提高商业乳业生产效率的方法均在本手稿中进行了介绍。实施系统的生殖管理计划，利用有效的TAI计划和优化的管理策略，可以产生高繁殖指数，并与被称为“高生育力周期”的高产奶量的健康奶牛相结合。这些概念背后的科学成果以及如何切实实施这些思想以提高商业乳业生产效率的方法均在本手稿中进行了介绍。