小尾寒羊同期发情技术优化及其血清生殖激素的变化

Optimization of estrus synchronization technology and changes of serum reproductive hormones in Small-tailed Han Sheep

为了优化绵羊同期发情技术,本试验分析了不同外源激素对小尾寒羊的同期发情效果,并进行生殖激素测定。将80只健康、空怀的经产小尾寒羊随机分为2组,每组4个重复,每个重复10只。采用单因素设计,分别用CIDR+PMSG、PG+PMSG进行同期发情处理,并在处理期间每组随机抽取4只小尾寒羊空腹颈静脉采血,采用放射免疫法测定血清中雌二醇(E2)、孕酮(P4)、促黄体素(LH)、促卵泡素(FSH)的浓度。结果表明:CIDR+PMSG组小尾寒羊同期发情率、受胎率分别为82.50%、75.00%,均显著高于PG+PMSG处理组(P<0.05);CIDR+PMSG组小尾寒羊颈静脉血液中E2浓度在撤栓24 h上升至峰值(8.64±0.13)pg/m L,显著高于撤栓时、撤栓48 h的浓度(P<0.05),P4浓度在撤栓7d显著高于撤栓24 h、撤栓48 h(P<0.05),LH、FSH浓度变化曲线与E2相似,都是在撤栓24 h显著升高;PG+PMSG组除LH在二次注射后的第2天、第3天显著升高(P<0.05),其余3种激素浓度差异不显著(P>0.05)。总之,与PG+PMSG相比,CIDR+PMSG可以显著提高小尾寒羊同期发情效率,并且发情高峰期在撤栓后的24 h前后,因此,人工输精选择在撤栓后12h^36h之间进行为佳。

This experiment was conducted to examine effects of estrus synchronization by using different exogenous hormones on serum concentrations of reproductive hormones in Small- tailed Han Sheep in order to optimize the method of estrus synchronization. Eighty healthy,non-pregnant,parous ewes were randomly assigned into 2 groups with 4 replicates per group and 10 ewes per replicate. Group 1 with CIDR＋PMSG,group 2 with PG＋PMSG for estrus synchronization,and blood samples were collected from 4 ewes,respectively. The serum estradiol（ E2）,progesterone（ P4）,luteinizing hormone（ LH） and follicle-stimulating hormone（ FSH） were measured by radioimmunoassay. The results showed that estrus synchronization and conception rates of the ewes with CIDR＋PMSG were 82. 50% and 75. 00%,respectively,significantly higher than that of PG ＋ PMSG group（ P〈0. 05）. In the CIDR＋PMSG group,the serum E2 concentration in the ewes in 24 hours after CIDR withdrawal rose to 8. 64±0. 13 pg / ml,which was significantly higher than that at the moment CIDR withdrawal and 48 hours after CIDR withdrawal（ P〈0. 05）. The serum P4 concentration in the ewes in 7 days was significantly higher than that at 24 hours and 48 hours after CIDR withdrawal（ P〈0. 05）. Serum concentrations of LH and FSH were significantly higher at 24 hours after CIDR withdrawal（ P〈0. 05）,which was similar to E2. In the PG＋PMSG group,serum concentrations of E2,P4,LH and FSH were not significant difference（ P〉0. 05）,except LH was significantly higher at 2 days and 3 days after treatment（ P〈0. 05）. These results indicated that CIDR＋PMSG could significantly improve the efficiency of estrus synchronization,and the estrus peak around at the 24 hours after CIDR withdrawal. Artificial insemination（ AI） should do among 12 hours to 36 hours after CIDR withdrawal.