IMMUNOREACTIVE LUTEINIZING HORMONE AND PROGESTERONE DURING PREGNANCY AND FOLLOWING GONADOTROPHIN ADMINISTRATION IN BEAGLE BITCHES

Abstract

ABSTRACT Immunoreactive canine luteinizing hormone (IRCLH) and progesterone were measured in the plasma of Beagle bitches. Changes in plasma hormone concentrations during pregnancy were similar to those seen in the non-pregnant animal during metoestrus. Administration of pregnant mares' serum gonadotrophin (PMSG) and human chorionic gonadotrophin (HCG) to anoestrous bitches induced oestrus. However, the duration of progesterone secretion was shorter than that seen in pregnant bitches. Treatment appeared to stimulate the secretion of IRCLH and in some animals plasma levels reached a maximum some weeks after the end of oestrus.