The induction of oestrus and ovulation in the bitch using pregnant mare serum gonadotrophin and human chorionic gonadotrophin.

Seventeen bitches (11 anoestrous, 4 prepubertal, 1 pregnant and 1 postpartum) were treated with pregnant mare serum gonadotrophin (110 iu/kg) at weekly intervals up to the occurrence of oestrus or a maximum of 3 treatments. Oestrus was induced in 8/11 anoestrous bitches only. The between bitch ovarian response was very variable. Ovulation occurred in 7/8 PMSG induced oestrous bitches. The 3 oestrous bitches treated with human chorionic gonadotrophin (500 iu) at the start of oestrus had a better ovulatory response than those treated with PMSG alone.