Superovulation in the cow with pregnant mare serum gonadotrophin: effects of dose and antipregnant mare serum gonadotrophin serum

beef cattle bovin de boucherie choix de la date conception conception rate corps jaune corpus luteum cows dosage ganado de carne graafian follicles immune serum immunserum ovaire ovaries ovarios ovulation performance de reproduction pms pmsg reproductive performance reproductividad suero inmune superovulation timing vaca vache