TRIALS OF GONADOTROPIN TO REGRESS OVARIAN CYSTS PROVOKED BY HORMONAL INDUCTION OF LACTATION

Successful induction of lactation in 5 nulliparous repeat breeding cows was achieved by administering diethyl stillboestrol (0.1 mg/kg B.W.) and hydroxyprogesterone caproate (0.25 mg/kg B.W.) for 3 days followed by reserpine (4 mg/day) for 4 days, and dexamethasone (16 mg/day) for one day. The treatment caused cystic ovarian condition in all the animals. Intravaginally progesteronesoaked sponges suppressed but did not eliminate the behavioural estrus. Administration of LHRH ($300{\mu}g$) regressed the cysts in all animals in the first instance but the cysts reappeared in 2 animals. One animal became pregnant and delivered a normal calf.