Efficacy of a Single Versus a Split Dose of PGF2α in a GnRH + PGF2α Synchronization Protocol in Lactating Angus and Cattle of Bos indicus Breeding
نویسندگان
چکیده
A modified GnRH+prostaglandin F2α (PGF2α) estrous synchronization protocol in combination with melengestrol acetate (MGA) was used at three locations using Angus (n=208), crossbred Bos indicus (n=294), and crossbred Bos indicus and Brahman cows (n=111) to evaluate the effectiveness of two PGF2α treatments to synchronize cows for artificial insemination (AI). On day 0 of the experiment all cows received 2 cc of GnRH and 7 d later, half the cows in each location received either 5 cc of PGF2α (single dose; LUTALYSE Sterile Solution) or 2.5 cc of PGF2α (split dose) on day 7 and 8. All cows received MGA on days 1 to 6 of the experiment at a rate of 0.5 mg/cow/d. Heat detection was conducted on days 7, 8, 9, and 10 of the experiment and cows were inseminated 8 to 12 h after an observed heat. Cows not observed in heat by day 10 of the experiment, were timed-AI and administered 2 cc of GnRH on day 10.
منابع مشابه
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