Abstract :
Estrus synchronization is a routine reproductive management tool for dairy producers. There are numbers of estrus synchronization programme available in dairy cattle using various hormones like progesterone, prostaglandin FGF2a and their various combinations with other hormones like estrogen and gonadotrophin releasing hormone (GnRH). Estrus synchronization can be completed with the prostaglandin PGF2a alone, but it requires the proper detection of the ovarian condition of the cattle as prostaglandin PGF2a is active in only functional corpus luteum in between 8 to 17 days of estrous cycle. The short time exposure of progesterone (less than 14 days) is useful for estrus synchronization. Progesterone or prostagland in based synchronization programme with addition of GnRH is helpful for better estrus synchronization. GnRH may be helpful to synchronize the estrous cycle in delayed pubertal heifers and post partum cows (Post partum anoestrus). Synchronization of estrus with GnRH-PGF2a protocol is preceded by progesterone treatment giving effective synchronization of estrus with high fertility rate.
Keyword :
Anoestrus, Estrus synchronization, Estrogen, Gonadotrophin hormone (GnRH), Prostaglandin (PGF2a), Progesterone