The present study was conducted to estimate incidence of late embryonic and early fetal mortalities (LEM/EFM) after embryo transfer (ET) and to investigate factors that could affect proportions of LEM/EFM in dromedary camels. The uteri of 180 donors were flushed at Day 9 post-mating and 1309 ETs were conducted in 886 recipient females in two breeding seasons (2014-2015 and 2015-2016). Pregnancy diagnosis was conducted at Day 10 after ET (Day 19 of gestation) by using the progesterone-ELISA test and by transrectal ultrasonography at Day 60 of gestation. Pregnancy rates at Days 19 and 60 and proportions of LEM/EFM were 54.5%, 34.1%, and 37.5%, respectively. Using logistic regression analysis for evaluations, shape of embryos had an effect (P < 0.01) on pregnancy rates at Days 19 and 60. Also, number of recovered embryos per uterine flushing and breeding season (year) had an effect (P < 0.05) on pregnancy rates at Day 19 and 60, respectively. Regarding rate of LEM and EFM, size of embryos and year of ET had effects (P < 0.01 and P < 0.05, respectively) on the values for these variables. In conclusion, there is a marked occurrence of LEM/EFM in recipient females between Days 20 and 60 of gestation in dromedary camels. The pregnancy rate after ET might be affected by the shape and number of recovered embryos and the year. In addition, the rate of LEM/EFM after ET might be affected by the year and size of the embryos.

本研究旨在估计胚胎移植 (ET) 后胚胎晚期和早期胎儿死亡 (LEM/EFM) 的发生率，并调查可能影响单峰骆驼 LEM/EFM 比例的因素。在交配后第 9 天冲洗了 180 名捐赠者的子宫，并在两个繁殖季节（2014-2015 和 2015-2016）对 886 名接受雌性进行了 1309 次 ET。妊娠诊断是在 ET 后第 10 天（妊娠第 19 天）通过使用孕酮-ELISA 测试和在妊娠第 60 天通过经直肠超声检查进行的。第 19 天和第 60 天的妊娠率以及 LEM/EFM 的比例分别为 54.5%、34.1% 和 37.5%。使用逻辑回归分析进行评估，胚胎形状有影响（P < 0.01) 对第 19 天和第 60 天的妊娠率的影响。此外，每个子宫潮红和繁殖季节（年）回收的胚胎数 分别对第 19 天和第 60 天的妊娠率产生影响 ( P < 0.05)。关于 LEM 和 EFM 的比率，胚胎大小和 ET 年份 对这些变量的值有影响（分别为P  < 0.01 和P < 0.05）。总之，在单峰骆驼妊娠 20 至 60 天之间，接受雌性的 LEM/EFM 显着发生。ET 后的妊娠率可能受恢复胚胎的形状和数量以及年份的影响。此外，ET 后 LEM/EFM 的比率可能受胚胎年份和大小的影响。