chapter  6
30 Pages

Current and Emerging Methods to Synchronize Estrus with Melengestrol Acetate (MGA)

A Review of the Estrous Cycle...............................................................................59 Development of Methods to Synchronize Estrus ...................................................60 Synchronization of Estrus and Ovulation with the GnRH-PG-GnRH Protocol ......................................................................61 Background and Development of Methods to Synchronize Estrous Cycles with MGA.............................................................62 The MGA-PG Protocol...........................................................................................64 Potential for Induced Estrous Cyclicity with Progestins........................................67 Using Reproductive Tract Scores in Heifers to Time Estrous Synchronization Programs with MGA.......................................................68 Effect of the MGA-PG Protocol on Estrous Synchronization and Conception Rate ...............................................................................................70 Effect of the MGA-GnRH-PG Protocol on Estrous Synchronization ..................72 A Modified MGA Protocol .....................................................................................75 Studies Designed to Shorten the Length of Treatment...........................................78 Summary ..................................................................................................................79 References................................................................................................................81