Thyroid in intermediary metabolism of the migratory redheaded bunting, Emberiza bruniceps (Brandt)

Effect of thyroidectomy and replacement therapy with L-T4, on liver and plasma biochemical constituents of E. bruniceps, was studied during January (recovery phase). Thyroidectomy elevated significantly the levels of plasma glucose, protein, cholesterol, diglyceride, hepatic cholesterol and depressed significantly hepatic free fatty acid without affecting liver and body weights. Treatment of thyroidectomized birds with L-T4 restored liver and plasma constituents, but had significantly depressed plasma phospholipid. These findings suggest that thyroid hormones are critically involved in lipo-regulatory mechanism(s) in E. bruniceps.