Supplemental progestin increases pregnancy rates in suckled beef cows

Abstract

In two experiments, combining a source of progestin with the ovulation synchronization protocol using gonadotropin-releasing hormone plus prostaglandin F2a (GnRH + PGF2a) tended to increase or statistically increase pregnancy rates in suckled cows compared to GnRH + PGF2a alone. These improvements were accomplished without any detected estrus when cows were inseminated and received a second injection of GnRH at 48 hr after PGF2a.