Adaptation Physiology Group, Wageningen University, Wageningen, The Netherlands.
Anim Reprod Sci. 2011 Apr;124(3-4):251-8. doi: 10.1016/j.anireprosci.2011.02.025. Epub 2011 Feb 23.
The oestrous cycle in pigs spans a period of 18-24 days. It consists of a follicular phase of 5-7 days and a luteal phase of 13-15 days. During the follicular phase, small antral follicles develop into large, pre-ovulatory follicles. Being a polytocous species, the pig may ovulate from 15 to 30 follicles, depending on age, nutritional status and other factors. During the luteal phase, follicle development is less pronounced, although there is probably a considerable turnover of primordial to early antral follicles that fail to further develop due to progesterone inhibition of gonadotrophic hormones. Nevertheless, formation of the early antral follicle pool during this stage probably has a major impact on follicle dynamics in the follicular phase in terms of number and quality of follicles. Generally, gilts are mated at their second or third estrous cycle after puberty. After farrowing, pigs experience a lactational anoestrus period, until they are weaned and the follicular phase is initiated, resulting in oestrus and ovulation 4-7 days after weaning. This paper describes the major endocrine processes during the follicular and luteal phases that precede and follow ovulation. The role of nutrition and metabolic status on these processes are briefly discussed.
猪的发情周期持续 18-24 天。它由 5-7 天的卵泡期和 13-15 天的黄体期组成。在卵泡期，小的窦卵泡发育成大的、排卵前的卵泡。作为一种多胎物种，猪可能会从 15 到 30 个卵泡中排卵，这取决于年龄、营养状况和其他因素。在黄体期，卵泡发育不太明显，尽管由于孕酮抑制促性腺激素，可能会有大量原始卵泡和早期窦卵泡发生转化，这些卵泡由于孕酮的抑制而无法进一步发育。然而，在这个阶段形成早期窦卵泡池可能会对卵泡期的卵泡动态产生重大影响，包括卵泡的数量和质量。一般来说，小母猪在青春期后的第二个或第三个发情周期进行配种。分娩后，猪会经历哺乳期乏情期，直到它们断奶，卵泡期开始，导致断奶后 4-7 天发情和排卵。本文描述了排卵前和排卵后的卵泡期和黄体期的主要内分泌过程。简要讨论了营养和代谢状态对这些过程的影响。
