![Sample our Environment & Agriculture journals, sign in here to start your access, latest two full volumes FREE to you for 14 days]({"type":"image" , "src" : "/sda/5934/TOC-Subject-Sample-2021-Environment-Agriculture.jpg"})
Abstract
Montiel, F., Galina, C., Rubio, I. and Corro, M. 2006. Factors affecting pregnancy rate of embryo transfer in Bos indicus and Bos taurus/Bos indicus cows. J. Appl. Anim. Res., 29: 149–152.
The present study was conducted to determine the factors affecting pregnancy rate after embryo transfer (ET) in cows from the tropics. Zebu (n=105, Experiment I) and Bos taurus/Bos indicus (n=110, Experiment II) potential recipients of embryos were synchronised with a norgestomet implant and received feed supplementation. In both experiments, recipients were divided in two groups: 1) subsequent spontaneous oestrus (SSO) and 2) synchronised oestrus (SO). At ET, recipients of Experiment I (n=50) and II (n=47) were transferred with a single frozen-thawed, in vitro fertilised Fl (Holstein/Zebu) embryo. Pregnancy rate for Experiment I and II was 16% and 36.2%, respectively. In Experiment I, pregnancy rate was affected by day of transfer (day 7 or day 8, P<0.05). In Experiment II, pregnancy rate was affected by oestrus type (SSO and SO), feed supplementation (with and without), and body condition score (low and high; P<0.05).