INDUCTION OF FOLLICULAR DEVELOPMENT IN SILVER FOXES (VULPES-VULPES) WITH EQUINE CHORIONIC-GONADOTROPIN (ECG) AND ANTIBODIES AGAINST ECG

Experiments were conducted that demonstrated that 1000 iu equine chori onic gonadotrophin (eCG) was effective in induction of follicular deve lopment and ovulation in silver foxes during anoestrus. This treatment resulted in large, unovulated follicles; thus, trials in which the ef fects of eCG were reduced or abrogated by antibodies against eCG were carried out. Passive immunization against eCG on days 3 and 4 after eC G treatment interfered with subsequent follicular development and prev ented ovulation. Treatment with eCG antibodies on days 5 or 7 after eC G treatment did not prevent ovulation and neutralization beginning on day 5 appeared to provide for the best ovulatory yield. The results su ggest that combinations of eCG and anti-eCG antibody may provide a use ful means of inducing ovarian activity in anoestrous foxes.