Dixon A B, Knights M, Pate J L, Lewis P E, Inskeep E K
Division of Animal and Veterinary Science, West Virginia University, Morgantown, WV 26506-6108, USA.
Reprod Domest Anim. 2006 Apr;41(2):142-8. doi: 10.1111/j.1439-0531.2006.00656.x.
Three experiments were conducted with a total of 1579 ewes to examine reproductive performance in response to synchronization of oestrus during the breeding season, using controlled internal drug releasing (CIDR-G) inserts in regimens designed to provide high concentrations of circulating progesterone. In experiment 1, treatment with two CIDR-G inserts for 12 days produced conception rate (79%) and prolificacy (1.9) to first service equivalent to breeding at natural oestrus (56% and 2.0, respectively). Pregnancy rates to two service periods were 90 and 79%, respectively. In experiments 2 and 3, progesterone was delivered by a single CIDR-G insert for 5 days in combination with prostaglandin F2alpha (PGF2alpha; 5 mg i.m., twice, 3 h apart) the day before (experiment 2), or at insert removal (experiment 3). The combined treatments improved rates of synchronization of oestrus (p<0.01) by 23 and 20% points, respectively, and pregnancy rates to the first service period by 19 (p<0.05) and 13 (p<0.01) percentage points, respectively, compared to treatment with PGF2alpha alone. It is concluded that the combination of treatment for 5 days with a CIDR-G insert and two injections of 5 mg PGF2alpha, the day before, or the day of insert removal, were effective treatments to obtain high fertility at synchronized oestrus in ewes during the breeding season.
进行了三项试验，共有1579只母羊参与，以研究在繁殖季节使用旨在提供高浓度循环孕酮的方案中，采用控制内部药物释放（CIDR-G）植入物进行发情同步处理后的繁殖性能。在试验1中，使用两个CIDR-G植入物处理12天，首次输精的受胎率（79%）和产羔率（1.9）与自然发情配种相当（分别为56%和2.0）。两个输精期的妊娠率分别为90%和79%。在试验2和试验3中，通过单个CIDR-G植入物提供5天孕酮，并在植入前一天（试验2）或取出植入物当天（试验3）联合使用前列腺素F2α（PGF2α；5毫克肌肉注射，两次，间隔3小时）。与单独使用PGF2α处理相比，联合处理分别使发情同步率提高了23和20个百分点（p<0.01），首次输精期的妊娠率分别提高了19个百分点（p<0.05）和13个百分点（p<0.01）。得出的结论是，在繁殖季节，用CIDR-G植入物处理5天并在植入前一天或取出植入物当天注射两次5毫克PGF2α的联合处理，是使母羊发情同步时获得高繁殖力的有效处理方法。
