Effect of human chorionic gonadotropin on serum levels of thyroid hormones during oestrus in goats.

摘要

The effects of HCG dose (550, 650 or 750 IU) and of the oestrous cycle on the serum concentrations of triiodothyronine (T3) and thyroxine (T4) in 40 goats were examined. Serum T3 and T4 levels differed significantly (P<0.05) among the days of the oestrous cycle in all the groups; the highest levels were observed on the day of oestrus and on the first day of the subsequent oestrous cycle. The levels were lower during other days of the oestrous cycle. No significant differences were observed in serumT3 and T4 levels amongst the treatment groups or between treated and control animals. Higher concentrations of T3 and T4 were found in the animals that received 750 IU HCG.