摘要
Artificial insemination is a key technique to increase reproductive efficiency and the genetic improvement in cattle. The first report of artificial insemination has been dated to more than 220 years ago; after that, many studies have been published, and this biotechnology is widely used in domestic animals. Despite the advances of embryo transfer programs in vivo and in vitro in cattle, artificial insemination still represents the main form of assisted reproduction in many herds, being one of the lowest cost strategies to improve genetic merit in the farms. Artificial insemination has many advantages compared to natural breeding, such as health benefits, e.g. control of infectious diseases; genetic improvement, e.g. use of genetically improved bulls; reproductive management improvements; and more stringent control of the zootechnical and economic features of the herd, e.g. standardized management and animals.
In addition, we highlight the main advances related to the use of artificial insemination in cattle, such as the development of other reproductive biotechniques, such as timed artificial insemination and resynchronization of estrus or ovulation. In addition, the sexed semen has evolved satisfactorily with promising results both in insemination and in embryo production. An important advance in artificial insemination is related to the hormonal control of the estrous cycle that allows the elaboration of highly efficient protocols for the synchronization of estrus and ovulation. The hormonal protocols have contributed to the dissemination of the artificial insemination by allowing the insemination of many females in a short period of time. Based on many studies evaluating timed artificial insemination protocols and early and accurate pregnancy diagnosis techniques, it was also possible to establish estrus and ovulation resynchronization strategies, which have greatly contributed to economic profitability. Finally, here we review many strategies associated with manipulation of the dominant follicle, estrus behavioral and antral follicle count have been elaborated and they represent an important progress to improve the use of timed artificial insemination in cattle. Therefore, this chapter aims to present the main advances of artificial insemination and timed artificial insemination, highlighting the technical parameters, advantages, and influencing factors, and to discuss practical and current strategies for the improvement of the herd via artificial insemination programs.
摘要译文
人工授精是提高生殖效率和牛遗传改善的关键技术。第一份人工授精的报告已在220多年前日期;之后，已经发表了许多研究，这种生物技术广泛用于家畜。尽管在体内和体外胚胎中胚胎转移计划的进展，但人工授精仍代表许多畜群中辅助繁殖的主要形式，是改善农场遗传优点的最低成本策略之一。与天然育种相比，人工授精具有许多优点，例如健康益处，例如健康益处。控制传染病;遗传改善，例如使用遗传改善的公牛;生殖管理改进;更严格控制群体的Zootechnical和经济特征，例如，标准化的管理和动物。此外，我们强调了与牛中人工授精的使用有关的主要进展，例如其他生殖生物技术的发展，如定时人工授精和雌性或排卵的重新同步。此外，性别精液已经令人满意地演变，有希望的授精和胚胎生产。人工授精中的一个重要进步与腐蚀性循环的激素控制有关，其允许制定高效方案用于同步的雌性和排卵。荷尔蒙方案通过在短时间内允许许多女性授精来促进人工授精的传播。基于许多研究评估定时人工授精协议和早期准确的妊娠诊断技术，也可以建立雌雄和排卵，这极大地促进了经济盈利能力。最后，我们审查了许多与操纵占优势卵泡的操作相关的策略，已经详细阐述了，它们代表了改善牛中定时人工授精的使用的重要进展。因此，本章旨在展示人工授精和定时人工授精的主要进步，突出了技术参数，优势和影响因素，并通过人工授精计划讨论了改善畜群的实用和目前策略。
Fábio Morotti.1;Elis Lorenzetti.2;3;Marcelo Marcondes Seneda.1. Artificial Insemination Program in Cattle. Sustainable Agriculture Reviews 54[M].DE: Springer, 2021: 1-53