摘要
The objective was to evaluate the effects of temporary calf removal (TCR), eCG administration, or both, in a progesterone-based protocol. Suckled Nellore cows (40–80 d postpartum, n = 443) with body condition scores from 2.0 to 3.5 (5-point scale) on three farms were all given a synchronizing protocol (PEPE). At the start (designated Day 0), cows were given an intravaginal device (1.0 g of progesterone) and 2.5 mg of estradiol benzoate (EB) im. On Day 8, the device was removed and cows were given PGF2α (150 μg of d-cloprostenol im), followed in 24 h by 1.0 mg EB im, and 30–36 h thereafter, fixed-time AI. The design was a 2 × 2 factorial; main effects were TCR (54–60 h; from device removal to FTAI) and eCG treatment (300 IU im, concurrent with PGF2α). Transrectal ultrasonography was done on Days −10 and 0 to detect anestrus (absence of a CL at both examinations) and ∼30 d after FTAI (pregnancy diagnosis). Data were analyzed by logistic regression. The following variables did not significantly affect pregnancy rates: farm, postpartum interval, cyclicity, inseminators, and semen (sire). Overall, 77% of the cows were deemed anestrus. Pregnancy rates were similar (P > 0.05) among treatment groups: Control (54/108 = 50.0%), TCR (44/106 = 41.5%), eCG (63/116 = 54.3%), and TCR + eCG (49/113 = 43.4%). Pregnancy rate was higher in multiparous than primiparous cows (186/360, 51.7% vs. 24/83, 28.9%, P < 0.01), but was not significantly affected by cyclicity status or body condition score. In conclusion, temporary calf removal, eCG, or both, did not significantly increase pregnancy rate to timed-insemination in a progesterone-based synchronization protocol in postpartum Nellore cows with acceptable body condition.
摘要译文
的目的是评价的临时小牛去除（TCR），心电图施用，或两者的影响，在一个孕酮为基础的协议。哺乳母牛内洛尔（40-80Ð产后，N \x3d 443），与身体状况评分从2.0至3.5（5分制）的三个农场都领到了一个同步协议（佩佩）。在启动（指定第0天），母牛给予阴道内装置（1.0克孕酮）和苯甲酸雌二醇（EB）IM 2.5毫克。第8天，该设备被删除，奶牛给予PGF 2克D-氯前列烯醇即时），随后在1.0毫克的EB即时24小时，此后30-36小时，固定时间的AI。设计是一个2×2因子;主要的影响是TCR（54-60 H;从设备删除到FTAI）和心电图治疗（300 IU IM，同时与PGF 210和0检测乏情（在两个考试缺少CL）和以下变量并没有显著影响怀孕率：农场，产后间隔，周期性，inseminators，和精液（父系）。总的来说，奶牛77％被认为乏。怀孕率相似（P在多子初产比牛（360分之186，51.7％和83分之24，28.9％，P受孕率较高最后，临时小牛除去，心电图，或两者没有显著增加受孕率定时人工授精产后奶牛内洛尔可接受的身体条件的孕激素为基础的同步协议。
V.G. Pinheiro[a]; A.F. Souza[a]; M.F. Pegorer[b]; R.A. Satrapa[a]; R.L. Ereno[b]; L.A. Trinca[c]; C.M. Barros[a]. Effects of temporary calf removal and eCG on pregnancy rates to timed-insemination in progesterone-treated postpartum Nellore cows[J]. Theriogenology, 2009,71(3): 519–524