Diaz T, Pancarci S M, Drost M, Schmitt E J, Ambrose J D, Fredriksson W E, Thatcher W W
Department of Dairy and Poultry Sciences, and University of Florida, Gainesville 32611-0920, USA.
J Dairy Sci. 2001 Jan;84(1):88-99. doi: 10.3168/jds.S0022-0302(01)74456-6.
Three experiments were conducted to evaluate the effect of an induced first wave persistent dominant follicle on folliculogenesis and ovulatory responses induced by FSH. On d 6 of a synchronized estrous cycle (d 0 = estrus), cows were treated with a Syncromate-B implant and two injections of PGF2, (25 mg, 0700 h; 15 mg, 1900 h, i.m.). Cows in the control group retained a first-wave persistent dominant follicle, but in the aspirated group, the first-wave dominant follicle was removed via transvaginal aspiration on d 10 (d 0 = estrus). Beginning on d 12, cows received 32 mg of FSH-P i.m. in decreasing doses at 12-h intervals over a 4-d period. On d 15, the Syncromate-B implant was removed, and cows were ovariectomized (experiment 1, n = 8) or inseminated (experiment 2, n = 11) at 10 and 22 h after the onset of estrus. Cows in experiment 3 received a used controlled intravaginal drug releasing (CIDR) device and two injections of PGF2alpha (25 mg, 0700 h; 15 mg, 1900 h; i.m.) on d 6. On d 8, the first-wave dominant follicle was aspirated (n = 6) or left intact (n = 5), and FSH treatment was initiated (20 mg of Folltropin in decreasing doses at 12-h intervals over a 4-d period), and on d 10 the used CIDR device was removed from all cows. Ovarian follicle size and number were examined daily by ultrasonography from d 5 of the estrous cycle. The persistent dominant follicle increased in size from 10.7 mm on d 5 to 15.4 mm on d 10 (experiments 1 and 2), and from 9 mm on d 5 to 20.4 mm on d 11 (experiment 3). From d 11 to 14, the number of class 1 (2 to 5 mm) follicles was lower in the aspirated group than in the control group; the number of class 2 (6 to 9 mm) follicles was higher on d 12 and 13 for the aspirated group (experiments 1 and 2). The number of class 3 (> or =10 mm) follicles was higher in the aspirated group on d 14 to 16, but the same on d 17. Ovarian and embryo responses to superovulation did not differ between groups. In experiment 3, the numbers of class 1, 2, and 3 follicles, as well as ovarian and embryo responses following ovulation did not differ between groups. Initiation of exogenous FSH treatment appears to override any systemic inhibitory effect that a persistent dominant follicle may be exerting at the pituitary and possibly the ovary.
进行了三项实验，以评估诱导产生的第一波持续优势卵泡对促卵泡素（FSH）诱导的卵泡发生和排卵反应的影响。在同步发情周期的第6天（第0天 = 发情期），给母牛植入Syncromate - B，并进行两次前列腺素F2α注射（25毫克，上午7点；15毫克，晚上7点，肌肉注射）。对照组的母牛保留第一波持续优势卵泡，但在抽吸组中，在第10天（第0天 = 发情期）通过经阴道抽吸去除第一波优势卵泡。从第12天开始，母牛在4天内每隔12小时肌肉注射一次32毫克的促卵泡素 - P（FSH - P），剂量递减。在第15天，取出Syncromate - B植入物，在发情开始后的10小时和22小时对母牛进行卵巢切除（实验1，n = 8）或授精（实验2，n = 11）。实验3中的母牛在第6天接受一个用过的阴道内药物缓释（CIDR）装置和两次前列腺素F2α注射（25毫克，上午7点；15毫克，晚上7点；肌肉注射）。在第8天，对第一波优势卵泡进行抽吸（n = 6）或保持完整（n = 5），并开始FSH治疗（20毫克促卵泡素，在4天内每隔12小时剂量递减），在第10天从所有母牛中取出用过的CIDR装置。从发情周期的第5天开始，每天通过超声检查卵巢卵泡的大小和数量。持续优势卵泡的大小从第5天的10.7毫米增加到第10天的15.4毫米（实验1和2），以及从第5天的9毫米增加到第11天的20.4毫米（实验3）。从第11天到第14天，抽吸组中1类（2至5毫米）卵泡的数量低于对照组；在第12天和第13天，抽吸组中2类（6至9毫米）卵泡的数量更多（实验1和2）。在第14天至第16天，抽吸组中3类（≥10毫米）卵泡的数量更多，但在第17天相同。各组之间对超排卵的卵巢和胚胎反应没有差异。在实验3中，各组之间1类、2类和3类卵泡的数量以及排卵后的卵巢和胚胎反应没有差异。外源性FSH治疗的开始似乎克服了持续优势卵泡可能在垂体以及可能在卵巢上施加的任何全身性抑制作用。
