Vol. 39, No. 1-2, 1995
Thyroid hormone metabolism in laying and in molted Muscowy ducks
Janan, J., Rudas, P., Bartha, T.
Department of Physiology and Biochemistry
University of Veterinary Science
1400 Budapest Pf. 2
Hungary
Summary
Serum thyroxine (T4), triiodothyronine (T3) concentrations, and T4 5`-monodeiodinase activity in liver homogenates were studied in laying and molted Muscovy duck flocks. Egg laying ducks had a significantly higher serum T4 and lower serum T3 concentrations than molted ducks. Liver T4 5`-monodeiodinase activity was higher in molted ducks than in laying ones. Our findings suggest that higher T3 observed in molted ducks involved in molting processes and it is necessary for heat production and regeneration of plumage. The increased activity of 5`-monodeiodinase is responsible for this process.
Key words: Muscovy duck; molt; serum thyroxine; triiodothyronine and liver deiodinase activity
References
Folia Veterinaria / 1995