PLASMA THYROXINE AND TRIIODOTHYRONINE LEVELS AFTER INDUCTION AND SYNCHRONIZATION OF ESTRUS IN THE ANESTROUS SEASON IN EWES

The thyroid hormonal status of ewes after induction and synchronizatio n of estrus in the anoestrous season was investigated by determination of plasma triiodorthyronine (T-3) and thyroxine (T-4) concentrations using radioimmunoassay (RIA). Samples of jugular Venous plasma were co llected on the day of sponge insertion (P), at estrus (day 0.) as well as 7, 14 and 18 days after estrus. Plasma T-3 and T-4 levels in the c ontrol group of anoestrous ewes were significantly higher than those i n the ewes after synchronization of estrus, except, for the level of T -3 on days 14. and 18. after estrus, and T-4 On the day of sponge inse rtion.