Fierro S, Viñoles C, Olivera-Muzante J
Secretariado Uruguayo de la Lana (S.U.L.), Área de Transferencia de Tecnología, Servando Gómez 2408, Montevideo, Uruguay.
Instituto Nacional de Investigación Agropecuaria (INIA), Programa Nacional de Carne y Lana, Tacuarembó, Uruguay.
Anim Reprod Sci. 2016 Apr;167:74-82. doi: 10.1016/j.anireprosci.2016.02.009. Epub 2016 Feb 10.
To determine estrous, ovarian and reproductive responses after different prostaglandin (PG)-based protocols, ewes were assigned to groups PG10, PG12, PG14 or PG16 (twoPG injections administered 10, 12, 14 or 16 days apart; respectively). Experiment I (n=132) was conducted to evaluate the estrous response, ovulation rate (OR), conception and fertility. Experiment II (n=24) was conducted to evaluate ovarian follicle growth, steroid concentrations and the interval from the second PG injection to estrus (PG-estrus) and ovulation (PG-ovulation). Estrous response was less with the PG16 (P<0.05) treatment, and the extent of estrous synchrony was greater with the PG10 and PG12 treatments. Ovarian follicle growth and the intervals for the variables PG-estrus, PG-ovulation and OR were similar among groups (P>0.05). From 8 to 4 days before estrus, progesterone (P4) concentrations were greater for the PG14 and PG16 than for the PG10 and PG12 (P<0.05) groups. There were more days where concentrations of P4 were above 3.18 nmol/L with the PG14 and PG16 than PG10 and PG12 (P<0.05) treatments. Use of the PG14 and PG16 treatments resulted in greater estradiol (E2) at estrus and 12h later than use of the PG10 and PG12 treatments. A positive correlation was observed between the duration of the luteal phase and maximum E2 concentrations, and between duration of the luteal phase and days with E2 concentrations above 10 pmol/L. Conception and fertility were greater with use of the PG14 compared with PG10 and PG12 (P<0.05) treatments. The administration of two PG injections 10, 12, 14 or 16 days apart resulted in different durations of the luteal phase that were positively associated with E2 concentrations and the reproductive outcome. The shorter luteal phases were associated with greater synchrony in time of estrus. The intervals for the variables PG-estrus, PG-ovulation and OR were similar among groups.
为了确定不同基于前列腺素（PG）的方案后的发情、卵巢和生殖反应，将母羊分为PG10、PG12、PG14或PG16组（分别间隔10、12、14或16天进行两次PG注射）。进行实验I（n = 132）以评估发情反应、排卵率（OR）、受孕率和繁殖力。进行实验II（n = 24）以评估卵巢卵泡生长、类固醇浓度以及从第二次PG注射到发情（PG-发情）和排卵（PG-排卵）的间隔时间。PG16处理的发情反应较小（P<0.05），而PG10和PG12处理的发情同步程度更高。各组之间卵巢卵泡生长以及PG-发情、PG-排卵和OR等变量的间隔时间相似（P>0.05）。在发情前8至4天，PG14和PG16组的孕酮（P4）浓度高于PG10和PG12组（P<0.05）。与PG10和PG12处理相比，PG14和PG16处理中P4浓度高于3.18 nmol/L的天数更多（P<0.05）。与使用PG10和PG12处理相比，使用PG14和PG16处理在发情时和12小时后的雌二醇（E2）水平更高。观察到黄体期持续时间与最大E2浓度之间以及黄体期持续时间与E2浓度高于10 pmol/L的天数之间呈正相关。与PG10和PG12处理相比，使用PG14处理的受孕率和繁殖力更高（P<0.05）。间隔10、12、14或16天进行两次PG注射导致黄体期持续时间不同，黄体期持续时间与E2浓度和生殖结果呈正相关。较短的黄体期与发情时间的更大同步性相关。各组之间PG-发情、PG-排卵和OR等变量的间隔时间相似。
