title: Timed embryo transfer programs for management of donor and recipient cattle.
abstract: Currently, timed ovulation induction and fixed-time artificial insemination (FTAI) in superstimulated donors and synchronization protocols for fixed-time embryo transfer (FTET) in recipients can be performed using GnRH or estradiol plus progesterone/progestin (P4)-releasing devices and prostaglandin F(2α) (PGF2α). The control of follicular wave emergence and ovulation at predetermined times, without estrus detection, has facilitated donor and recipient management. However, because Bos taurus cows have subtle differences in their reproductive physiology compared with Bos indicus cattle, one cannot assume that similar responses will be achieved. The present review will focus on the importance of orchestrating donor and recipient management to assure better logistics of procedures to achieve more desirable results with embryo collection and transfer. In addition, this will provide clear evidence that the use of FTAI in superstimulated donors and FTET in embryo recipients eliminates the need to detect estrus with satisfactory results. These self-appointed programs reduce labor and animal handling, facilitating the use of embryo transfer in beef and dairy cattle.
authors.affiliation: Departamento de Reprodução Animal, FMVZ-USP, São Paulo-SP, Brazil. barusell@usp.br
authors.forename: P S
authors.initials: PS
authors.lastname: Baruselli
authors.forename: R M
authors.initials: RM
authors.lastname: Ferreira
authors.forename: J N S
authors.initials: JN
authors.lastname: Sales
authors.forename: L U
authors.initials: LU
authors.lastname: Gimenes
authors.forename: M F
authors.initials: MF
authors.lastname: Sá Filho
authors.forename: C M
authors.initials: CM
authors.lastname: Martins
authors.forename: C A
authors.initials: CA
authors.lastname: Rodrigues
authors.forename: G A
authors.initials: GA
authors.lastname: Bó
mesh_terms: D000818:Animals; D002417:Cattle; D004624:Embryo Transfer / Q000379:methods / Q000662:veterinary*; D004973:Estrus Synchronization; D005260:Female; D007315:Insemination, Artificial / Q000379:methods / Q000662:veterinary; D010062:Ovulation Induction / Q000379:methods / Q000662:veterinary; D011247:Pregnancy; D012621:Seasons; D013997:Time Factors