Blondin P, Guilbault L A, Sirard M A
Département des Sciences Animales, Université Laval Québec, Canada.
Theriogenology. 1997 Oct 1;48(5):803-13. doi: 10.1016/s0093-691x(97)00303-8.
Superovulation alone may not be enough to result in developmentally competent oocytes. The objective of this study was to determine if a time interval between FSH administration and slaughter and between slaughter and oocyte recovery could increase the percentage of embryos. Beef heifers (n = 20) were superovulated with 1 bolus injection of 25 mg, im FSH-P diluted in saline and then slaughtered at 24, 48 or 72 h after FSH injection and the ovaries transported to the laboratory at 30 degrees C. For 6 of the heifers that received FSH-P and were then culled at 48 h post treatment, oocytes were recovered 1 to 2 h post slaughter from the first ovary and 4 to 5 h from the second ovary. Ovaries from untreated cows were collected and served as controls. The results indicated that FSH-P and culling at 48 h produced 35% >/= 32-cell embryos, significantly more than FSH-P and culling at 24 and 72 h (19 and 14%, respectively; P < 0.05). Furthermore, FSH-P and culling at 48 h produced 25% >/= 64-cell embryos, significantly more than FSH-P and culling at 24 and 72 h and the nontreatment control group (5, 7 and 15%, respectively; P < 0.05). The FSH-P group culled at 48 h produced more >/= 32-cell embryos, with an average of 84 +/- 5 cells/embryo, than the treated groups culled at 24 and 72 h and the untreated group (52 +/- 6, 60 +/- 5 and 63 +/- 3, respectively; P < 0.01). Finally, oocytes left in the postmortem ovaries for 4 to 5 h resulted in higher rates (51% and 41%) of >/= 32- and >/= 64-cell embryos, respectively, compared with that of the untreated control animals (29 and 18%; P < 0.05), but these rates were not different from oocytes left in ovaries for 1 to 2 h (33 and 24%). It is concluded that culling at 48 h after FSH treatment, as well as the conditioning effect on oocytes in warm postmortem ovaries for 4 to 5 h, increases the number of competent oocytes.
单纯的超排卵可能不足以产生发育能力良好的卵母细胞。本研究的目的是确定促卵泡素（FSH）给药与屠宰之间以及屠宰与卵母细胞回收之间的时间间隔是否能提高胚胎的百分比。用1次大剂量注射25mg溶解于盐水中的FSH-P对20头肉用小母牛进行超排卵处理，然后在FSH注射后24、48或72小时屠宰，卵巢在30摄氏度下运至实验室。对于6头接受FSH-P处理并在处理后48小时被淘汰的小母牛，在屠宰后1至2小时从第一个卵巢回收卵母细胞，4至5小时从第二个卵巢回收。收集未处理母牛的卵巢作为对照。结果表明，FSH-P处理并在48小时屠宰产生的≥32细胞胚胎比例为35%，显著高于FSH-P处理并在24和72小时屠宰的情况（分别为19%和14%；P<0.05）。此外，FSH-P处理并在48小时屠宰产生的≥64细胞胚胎比例为25%，显著高于FSH-P处理并在24和72小时屠宰的情况以及未处理对照组（分别为5%、7%和15%；P<0.05）。在48小时被淘汰的FSH-P处理组产生的≥32细胞胚胎更多，平均每个胚胎有84±5个细胞，高于在24和72小时被淘汰的处理组以及未处理组（分别为52±6、60±5和63±3；P<0.01）。最后，与未处理的对照动物相比，死后卵巢中的卵母细胞在4至5小时后产生的≥32细胞胚胎和≥64细胞胚胎的比例分别更高（分别为51%和41%）（未处理对照动物为29%和18%；P<0.05），但这些比例与在卵巢中放置1至2小时的卵母细胞产生的比例（33%和24%）没有差异。得出的结论是，FSH处理后48小时屠宰以及死后温暖卵巢中卵母细胞4至5小时的条件作用会增加有能力的卵母细胞数量。
