The study was conducted to evaluate two protocols for synchronization of estrus in embryo recipients on the utilization rate throughout the year, as well as costs and the reproductive characteristics of synchronized animals. The treatments were: syncronization to transfer fixed-time with the use of implants of progesterone and oestradiol, and synchronization with prostaglandin and heat detection. 2947 embryo recipients were synchronized, and the rate of utilization was 83.24% in treatments 1 and 60.73% in treatments 2. The corpus luteum were evaluated on the day of embryo transfer, yielding 63.73% of ovulation in the right ovary. The utilization rate did not differ among months. The protocol at fixed time showed higher cost (U.S. $ 10.51 vs 2.03) than the use of prostaglandins and heat detection, but the utilization rate was higher . The utilization rates of the recipients do not vary throughout the year, when observing the conditions of nutrition and appropriate management for bovine embryo recipients.
corpus luteum; embryo transfer; prostaglandins; recipients