King K K, Seidel G E, Elsden R P
J Anim Sci. 1985 Oct;61(4):747-57. doi: 10.2527/jas1985.614747x.
Data were obtained from 1,908 pregnancies resulting from bovine embryo transfer procedures. Responses examined included sex ratio, fetal, neonatal and preweaning death losses, birth weight and calving assistance. The sex ratio for 1,751 embryo transfer calves examined was 51.11% males. Cows older than 10 yr that had become repeat breeders produced more (P less than .05) male calves than other donors. Breed of embryo, age and quality of embryos at the time of transfer, embryo storage time from collection to transfer, asynchrony of recipient with donor estrus and number of palpable corpora lutea in superovulated donors were not related to sex ratio (P greater than .05). The abortion rate between 2 and 3 mo of gestation in embryo transfer recipients was 3.15%, and between 3 to 7 mo, 2.14%. Neonatal and preweaning losses for 1,682 calves with complete information were 1) congenital defects, .54%; 2) death due to premature birth (7 to 8 mo of gestation), .18%; 3) dystocia-related deaths, 2.38%; 4) deaths of unknown causes at birth, 2.14%; 5) deaths of unknown causes from 24 h after birth to weaning, 1.43%; 6) deaths due to calfhood diseases, 1.25% and 7) deaths due to environmental factors, 1.13%. Total losses of 2-mo pregnancies due to abortion or death of calves or recipients were 14%. Birth weight of embryo transfer calves changed .29 kg/d of deviation from average gestation length (P less than .005) for pregnancies within breeds. Birth weight was also affected (P less than .005) by donor breed and recipient breed and age. Male calves averaged 2.19 kg heavier (P less than .005) than females. Calving assistance was affected by donor breed; Angus calves required the least assistance (P less than .005). Hereford, Holstein and Limousin calves were similar and intermediate; Simmental calves needed the most calving assistance. Recipient breed and age influenced calving ease, with younger recipients of Angus and Hereford descent requiring more assistance (average calving score, 2.1) than both cow (1.3) and heifer (1.5) recipients of the larger Continental European breeds. Characteristics of 305 non-embryo transfer calves were not significantly different from 185 embryo transfer calves from the same farms. We conclude that embryo transfer calves did not differ from the non-embryo transfer population in any of the characteristics studied.
数据来自1908例牛胚胎移植程序所产生的妊娠。所检查的反应包括性别比例、胎儿、新生儿和断奶前死亡损失、出生体重和产犊辅助情况。对1751头经胚胎移植出生的犊牛的性别比例检查显示，雄性占51.11%。10岁以上的经产母牛所产雄性犊牛比其他供体更多（P小于0.05）。胚胎品种、移植时胚胎的年龄和质量、从采集到移植的胚胎储存时间、受体与供体发情的不同步性以及超排供体中可触及黄体的数量与性别比例无关（P大于0.05）。胚胎移植受体在妊娠2至3个月时的流产率为3.15%，3至7个月时为2.14%。1682头有完整信息的犊牛的新生儿和断奶前损失情况如下：1）先天性缺陷，0.54%；2）早产（妊娠7至8个月）死亡，0.18%；3）难产相关死亡，2.38%；4）出生时不明原因死亡，2.14%；5）出生后24小时至断奶时不明原因死亡，1.43%；6）犊牛期疾病死亡，1.25%；7）环境因素死亡，1.13%。因流产或犊牛或受体死亡导致的2个月妊娠的总损失为14%。同一品种内，胚胎移植犊牛的出生体重随妊娠长度偏离平均水平每增加1天变化0.29千克（P小于0.005）。出生体重还受供体品种、受体品种和年龄的影响（P小于0.005）。雄性犊牛平均比雌性重2.19千克（P小于0.005）。产犊辅助情况受供体品种影响；安格斯犊牛所需辅助最少（P小于0.005）。海福特、荷斯坦和利木赞犊牛情况相似且居中；西门塔尔犊牛需要的产犊辅助最多。受体品种和年龄影响产犊难易程度，安格斯和海福特血统的年轻受体比欧洲大陆大型品种的母牛（平均产犊评分1.3）和小母牛（平均产犊评分1.5）需要更多辅助（平均产犊评分2.1）。来自同一农场的305头非胚胎移植犊牛的特征与185头胚胎移植犊牛无显著差异。我们得出结论，在所研究的任何特征方面，胚胎移植犊牛与非胚胎移植群体没有差异。
