Gonadotropin priming before OPU: What are the benefits in cows and calves?

Oocyte pick up (OPU) coupled with IVP produce over 1 million cattle embryos per year and has been most successful in Bos indicus derived breeds that contain large numbers of antral follicles on their ovaries. More recently, this technology has been applied on a large scale to Bos taurus cattle, where hormone manipulation is generally employed to improve the developmental competence of the COCs. Hormone manipulation, and specifically the use of FSH priming before OPU, has been strategically used in the intensively managed dairy cow, where genomic evaluation and juvenile IVP can produce additional significant genetic gains. •The number of oocytes collected at OPU is determined by the number of antral follicles on the ovary.•FSH priming improves the developmental competence of the oocyte in Bos taurus cattle.•FSH priming is necessary for juvenile in vitro embryo production programs.•FSH priming may not be required in Bos indicus in vitro embryo production programs.