【摘要】 为研究与优化不同同期发情方案对肉用母牛繁殖受胎率的影响。本研究在半放牧半舍饲模式下分别应用Ovsynch法、二次PG法、CIDR+PG法、CIDR+PG+GnRH法同期发情方案对夏洛莱牛、新疆褐牛、西门塔尔牛及相关杂交牛进行处理，在AI后通过直肠触诊和超声检查对牛进行妊娠诊断。结合PG剂量与BCS对受胎率统计分析得出，Ovsynch组、二次PG组分别与CIDR+PG组、CIDR+PG+GnRH组受胎率差异显著(P<0.05),在应用CIDR进行同期处理的牛群中，BCS<3组与其他三组受胎率差异显著(P<0.05);BCS≥8组与其他三组受胎率差异显著(P<0.05)。这些结果表明，不同同期发情方案对牛受胎率有显著影响，而BCS对受胎率也有一定影响。本研究为半放牧半舍饲模式下肉用母牛同期发情方案的选择与优化提供了参考。更多还原

【Abstract】 To study and optimize the effects of different estrus synchronization schemes on the reproductive conception rate of beef cattle. The simultaneous estrus schemes of Ovsynch method, secondary PG method, CIDR+PG method, CIDR+PG+GnRH method were used to treat the Charolai cattle, Xinjiang brown cattle, Simmental cattle and related hybrid cattle in a semi grazing and semi house feeding model. The pregnancy diagnosis of the cattle was performed by rectal palpation and ultrasound examination after AI in half grazing feeding mode Ovsynch method. Based on the statistical analysis of conception rate by combining PG dose and BCS, it was found that there was a significant difference in conception rate between the Ovsynch group and the secondary PG group compared to the CIDR+PG group and the CIDR+PG+GnRH group(P<0.05). In the cattle herd treated with CIDR during the same period, the BCS<3 group had a significant difference in conception rate compared to the other three groups(P<0.05). The difference in conception rate between the BCS≥8 group and the other three groups was significant(P< 0.05). These results indicated that different estrous synchronization programs had significant effects on cattle conception rate, while BCS also had some effects on conception rate. This research provided a reference for the selection and improvement of estrus synchronization programs for beef cattle under the condition of semi-grazing and semi house feeding modes.更多还原