PLASMA THYROID-HORMONE STATUS OF DELAYED PUBERTAL BUFFALO HEIFERS BEFORE AND AFTER TREATMENT WITH NONPITUITARY GONADOTROPINS

Thyroid hormones of 10 delayed pubetral buffalo heifers maintained at the University dairy farm were studied before and after treatment with non-pituitary gonadotrophins (n = 8), viz. 1000 IU PMSG followed by 1 500 IU hCG, after oestrus detections, both i/m. Both samples were coll ected at weekly interval before the treatment and daily thereafter to cover one oestrous cycle. Plasma was stored at -20 degrees C. Pretreat ment concentration (ng/ml) of plasma triiodothyronine (T-3) and thyrox ine (T-4) were 0.73+/-0.02 and 52.09+/-1.17, respectively, which start ed increasing after the treatment and reached a significantly high (P< 0.05) level of 1.12+/-0.03, 62.76+/-2.39 ng/ml during oestrus phase. T hereafter plasma T-3 and T-4 decreased nonsignificantly to 1.07+/-0.03 and 56.57+/-2.14 during dioestrus phase.