Control of Oestrus in Sheep

Application of Controlled Reproduction to Sheep Flocks in Newfoundland

“…Of the compounds tested, fluorogestone acetate (FGA (9a-fluro-1 1B-hydroxy-I 7 a-acetoxy-pregn-4-ene-3,20-dione (SC 9880), G. D. Searle and Co., Chicago, Ill.; Chronogest, In-tervet S. A. Angers, France), which has a potency 25 times that of progesterone in the inhibition of ovulation (Shelton 1965; Robinson 1965) has been the most widely used. Since the mid-1960s, research based on the use of intravaginal sponges impregnated with FGA has been actively pursued in Ireland (Gordon 1963(Gordon ,1971, and in France (Colas 1975; Cognie 1971, l9'7'l) with the result that an effective and simple method for the synchronous induction of estrus and ovulation in sheep is now available for commercial use in a number of western European countries which can be applied year round in sheep in all physiological states (Mauleon 1979;Robinson 1979 so (3) 31 (6) r6e (4) 36 (t) re (8) 40 (9) r46 (5) 40 (10) 43 (1 1 Gordon (19'15) and Quirke (1919) …”