背景:大范围的排卵分布是绵羊发情同步(ES)和固定时间授精(FTI)后建立妊娠的主要制约因素。
目的:使用两种不同的阴道装置确定ES后的排卵时间(OVT),它与孕酮和冷冻/解冻精液FTI受孕的关系。
方法:使用受控内部药物释放(CIDR)(母羊,n=6;母羊,n=5)或阴道海绵(母羊,n=6;母羊,n=5)插入12天,在设备移除时加上马绒毛膜促性腺激素(eCG)(第0天)。使用经阴道探针在-12、0和30-33、53小时测量卵巢卵泡的大小,并每3-4小时持续直到eCG治疗后75小时。在-12、0、+2和+11测量血清孕酮量。腹腔镜FTI在60.5±0.5h完成。
结果:与海绵治疗的女性相比,TheCIDR治疗组开始和完成排卵更早(中位数:64vs.71h;p<0.05)。与海绵处理组的母羊相比,母羊的排卵时间更早(66.71vs.71.5;p=0.017)。排卵卵泡和黄体的平均大小不受设备类型的影响。与取出装置时的海绵治疗组相比,CIDR组的孕酮含量更高(2.68±0.12vs.0.30±0.01ng/mL;p<0.001)。该概念在2/10和5/11的海绵和CIDR治疗的女性中得到证实,分别。
结论:孕激素的类型影响OVT,因此,FTI与冷冻/解冻精液的结果。FTI的最佳时间跨度应根据非繁殖季节的设备类型进行选择。
Wide range of ovulation distribution is the main restricting factor in establishing the pregnancy following oestrus synchronization (ES) and fixed time insemination (FTI) in sheep.
Determining the ovulation time (OVT) following ES with two different vaginal devices, its relation to progesterone and conception upon FTI with frozen/thawed semen.
Oestrus was synchronized using either controlled internal drug release (CIDR) (ewe, n = 6; ewe lamb, n = 5) or vaginal sponge (ewe, n = 6; ewe lamb, n = 5) insertion for 12 days, plus Equine chorionic gonadotropin (eCG) at devices removal (Day 0). Sizes of the ovarian follicles were measured using transvaginal probe at -12, 0 and 30-33, 53 h and continued every 3-4 h until 75 h after eCG treatment. Serum progesterone amounts were measured at -12, 0, +2 and +11. Laparoscopic FTI was done at 60.5 ± 0.5 h.
The CIDR-treated group initiated and completed ovulations earlier compared to sponge-treated females (median: 64 vs. 71 h; p < 0.05). Ewe lambs were ovulated earlier compared to ewes in the sponge-treated group (66.71 vs. 71.5; p = 0.017). Mean sizes of ovulatory follicles and corpora lutea were not affected by device types. Higher amounts of progesterone were observed in CIDR group compared to sponge-treated group at device removal (2.68 ± 0.12 vs. 0.30 ± 0.01 ng/mL; p < 0.001). The conception was confirmed in 2/10, and 5/11 females of sponge and CIDR-treated females, respectively.
Types of progestogens influence the OVT, and consequently the result of FTI with frozen/thawed semen. The optimum timespan for FTI should be chosen according to the device types during non-breeding season.