Britt J H, Armstrong J D, Cox N M, Esbenshade K L
J Reprod Fertil Suppl. 1985;33:37-54.
Follicular development during early lactation in the sow is characterized by a large population of small-sized follicles and a small population of medium-sized follicles. As lactation progresses there is a gradual shift in number of follicles into medium- or large-sized categories and the percentage of follicles classified as atretic declines. Weaning at birth often leads to aberrant follicular development, apparently because the positive feedback response of LH to oestradiol does not occur during the first week post partum. Secretion of LH during lactation is primarily controlled by suckling intensity of the litter while FSH is controlled by a nonsteroidal ovarian factor, presumably inhibin. Suckling apparently limits secretion of GnRH and weaning leads to an increase of GnRH within the hypothalamus coincident with an increase of LH in the anterior pituitary and plasma and increased follicular growth. Follicular development during both lactation and post-weaning anoestrus can be stimulated by exogenous gonadotrophins and pulsatile administration of GnRH. Factors such as nutrition, season, boar exposure, litter size and split weaning affect follicular development during lactation and after weaning, probably because they affect secretion of LH.
母猪泌乳早期的卵泡发育特点是大量小卵泡和少量中等大小卵泡。随着泌乳进程推进，卵泡数量逐渐向中等或大卵泡类别转变，闭锁卵泡的百分比下降。产后第一周内，出生时断奶常导致卵泡发育异常，这显然是因为促黄体生成素（LH）对雌二醇的正反馈反应未发生。泌乳期间LH的分泌主要受仔猪吮乳强度控制，而促卵泡生成素（FSH）受一种非甾体类卵巢因子（可能是抑制素）控制。吮乳显然会限制促性腺激素释放激素（GnRH）的分泌，断奶会导致下丘脑内GnRH增加，同时垂体前叶、血浆中的LH增加以及卵泡生长加快。泌乳期和断奶后乏情期的卵泡发育都可通过外源性促性腺激素和GnRH脉冲给药来刺激。营养、季节、接触公猪、窝仔数和分批断奶等因素会影响泌乳期和断奶后的卵泡发育，可能是因为它们影响LH的分泌。
