Estrous synchronization in cattle, sheep and goat

Abstract

Synchronization of estrous refers to manipulating the estrous cycle or induction of estrous to bring a large number or group of female animals into estrous at a short, determined time. An estrous cycle is a rhythmic event in the female animal from one estrous phase to the next. The normal estrous cycle length is 21 days in cows, 20 days in doe, and 17 days in the ewe. The hormones used in estrous synchronization are estrogen, progesterone, GnRH, and prostaglandin. Estrous synchronization helps shorten the breeding period instead of females being bred over a period of normal length, and this depends on the treatment protocols to be followed. Combining GnRH with prostaglandin F2α (PGF2α) and a progesterone-based synchronization program has shown a novel direction in cattle's estrous synchronization, which causes manipulation in follicular development. Estrous synchronization protocol should be followed based on managemental capabilities and expectations of the farmer. This review article was compiled to summarize the protocols used for estrous synchronization in different species.