适龄母牛适时与定时输精技术试验研究

Experimental Study on Timely and Timed Insemination Techniques for Eligible Cows

中文关键词: 肉牛  同期发情处理  适时输精  定时输精

英文关键词: beef cattle  estrus synchronization  timely ejaculation  timed insemination

中文摘要:

      为实现“半舍饲+半放牧”和舍饲地区母牛短时间内发情并受胎，探索了适合于哈密地区肉牛同期发情适时输精和同期排卵 定时输精较佳的技术处理方案。试验将60头适龄西门塔尔杂交母牛分为3组，分别采用3 种不同阶段同期发情程序进行处理，其中Ⅰ组采用1次前列腺素（PGF_2α）法，Ⅱ组采用2次PGF_2α法，Ⅲ组采用置入药物缓释装置(CIDR)＋PGF_2α法，比较各处理的发情率和情期受胎率。另选择44头适龄母牛并分为2组，采用2 种同期排卵-定时输精方法进行处理，其中Ⅳ组采用促黄体素释放激素A3(LHRH-A3)＋CIDR+PGF2α＋LHRH-A3法，Ⅴ组采用戈那瑞林(GnRH)＋CIDR＋PGF_2α＋GnRH法，比较2个处理的生殖激素水平变化情况及发情率和情期受胎率。结果表明，Ⅰ、Ⅱ、Ⅲ组母牛发情时间大多集中在同期发情处理后40～55 h，总发情率分别为75.0%、84.2%和90.5%，其中Ⅲ组显著高于Ⅰ组和Ⅱ组(P＜0.05)；发情母牛经人工授精后，Ⅲ组情期受胎率显著高于Ⅰ组和Ⅱ组(P＜0.05)，达到85.7%。2种同期排卵 定时输精处理中，Ⅳ组发情率比Ⅴ组高3.6%，情期受胎率比Ⅴ组高2.3%，但差异均不显著(P＞0.05)。综上，同期发情技术2 次PGF2α法效果良好且成本低，适用于集中人工授精；同期排卵 定时输精宜采用Ⅳ组方法，受胎率高，较为经济，适宜舍饲肉牛场应用。

英文摘要:

      In order to achieve the “semi-house feeding and semi-grazing” and the short-term estrus and conception of cows in house feeding areas,this study explored the optimal technical treatment schemes for estrus synchronization and timely insemination in beef cattle in Hami region,as well as synchronized ovulation timed insemination.The experiment divided 60 eligible Simmental hybrid cows into three groups and treated them with three different stages of estrus synchronization programs.Group Ⅰ used one session of prostaglandin (PGF2α) method,Group Ⅱ used two sessions of PGF2α method,and Group Ⅲ used drug delivery device (CIDR)+PGF2α method.The estrus rate and conception rate during estrus were compared among the treatments.An additional 44 eligible cows were randomly assigned to two groups.Two methods of simultaneous ovulation and timed insemination were used for treatment.Group Ⅳ used luteinizing hormone releasing hormone A3 (LHRH-A3)+CIDR+PGF2α+LHRH-A3 method,while Group Ⅴ used gonadotropin (GnRH)+CIDR+PGF2α+GnRH method. The changes in reproductive hormone levels,estrus rate,and conception rate during estrus were compared between the two treatments.The results indicated that,the estrus time of cows in groups Ⅰ,Ⅱ,and Ⅲ is mostly concentrated between 40-55 hours after synchronous estrus treatment,with total estrus rates of 75.0%,84.2%,and 90.5%,respectively.Among them,Group Ⅲ was significantly higher than Group Ⅰ and Group Ⅱ (P<0.05),while there was no significant difference between Group Ⅱ and Group Ⅲ(P>0.05).After artificial insemination,the conception rate of estrous cows in Group Ⅲ was significantly higher than that in Group Ⅰ and Group Ⅱ (P<0.05),reaching 85.7%.Among the two synchronous ovulation timed insemination procedures,the estrus rate of group Ⅳ was 3.6% higher than that of group Ⅴ,the conception rate during the estrus period was 2.3% higher than that of group Ⅴ,but the differences were not significant (P>0.05).In summary,the “2-time PG” method of synchronous estrus technology is effective and cost-effective,and is suitable for the promotion and application of centralized artificial insemination.Simultaneous ovulation and timed insemination should use group Ⅳ method,which has a high conception rate,is more economical,and suitable for use in livestock farms.