Wiesak T, Hunter M G, Foxcroft G R
AFRC Research Group on Hormones and Farm Animal Reproduction, University of Nottingham, Faculty of Agricultural and Food Science, Sutton Bonington, UK.
J Reprod Fertil. 1990 Jul;89(2):633-41. doi: 10.1530/jrf.0.0890633.
Ovaries were obtained from naturally cyclic pigs on Days 16-17, 18, 19, 20 and 21 of the oestrous cycle and on the basis of observed follicular characteristics were assigned as representative of the early (Group 1), mid- (Groups 2 and 3) or late (after LH; Group 4) follicular phase. Follicular development in cyclic gilts was compared with that in ovaries obtained from late prepubertal gilts 36 (Group 5) or 72 (Group 6) h after treatment with 750 i.u. PMSG alone, or with a combination of 500 i.u. hCG 72 h after PMSG and slaughter 30-40 h later (Group 7). After dissection of all follicles greater than 2 mm diameter, follicular diameter, follicular fluid volume, follicular fluid concentrations of progesterone, oestradiol and testosterone, and the stage of oocyte maturation were determined. Combined PMSG/hCG treatment of immature gilts resulted in a pattern of follicular development different from that in naturally cyclic gilts during the follicular phase. Overall exogenous gonadotrophin treatment also increased (P less than 0.001) the variability in follicular diameter and fluid volume. Comparisons between appropriate groups also established differences in the variability of both morphological (diameter and volume, Group 1 vs Group 5; P less than 0.05) and biochemical development (follicular fluid oestradiol, Group 3 vs Group 6 and Group 4 vs Group 7; both P less than 0.05). Such differences in both morphological and biochemical characteristics between cyclic and PMSG/hCG-treated gilts were particularly evident in the population of larger (greater than 6 mm) follicles. These results indicate that the pattern of follicular development in naturally cyclic and in PMSG/hCG-treated gilts is dissimilar and suggests that the ovaries of gonadotrophin-treated prepubertal gilts are functionally different from the ovaries of mature females.
在发情周期的第16 - 17天、18天、19天、20天和21天从自然发情周期的母猪获取卵巢，并根据观察到的卵泡特征将其指定为卵泡早期（第1组）、中期（第2组和第3组）或晚期（促黄体生成素之后；第4组）的代表。将发情周期母猪的卵泡发育与在单独用750国际单位孕马血清促性腺激素（PMSG）处理36小时（第5组）或72小时（第6组）后，或在PMSG处理72小时后再用500国际单位人绒毛膜促性腺激素（hCG）处理并在30 - 40小时后屠宰的接近青春期后期的小母猪的卵巢中的卵泡发育进行比较（第7组）。解剖所有直径大于2毫米的卵泡后，测定卵泡直径、卵泡液体积、卵泡液中孕酮、雌二醇和睾酮的浓度以及卵母细胞成熟阶段。对未成熟小母猪进行PMSG/hCG联合处理导致卵泡发育模式与发情周期自然发情的母猪在卵泡期的模式不同。总体而言，外源性促性腺激素处理也增加了（P < 0.001）卵泡直径和卵泡液体积的变异性。适当组之间的比较还确定了形态学（直径和体积，第1组与第5组；P < 0.05）和生化发育（卵泡液雌二醇，第3组与第6组以及第4组与第7组；两者P < 0.05）变异性的差异。发情周期母猪与PMSG/hCG处理的小母猪在形态学和生化特征上这种差异在较大（大于6毫米）卵泡群体中尤为明显。这些结果表明自然发情周期和PMSG/hCG处理的小母猪的卵泡发育模式不同，并表明促性腺激素处理的接近青春期后期小母猪的卵巢在功能上与成熟雌性的卵巢不同。
