Thyroxine-Induced Molting and Gonadal Functions of Laying Hens
In most avian species, molting and feather regeneration are related to breeding or seasonal changes. In addition to spontaneous molting, forced molting of laying domestic fowls is induced by a combination of food-water restriction and short photoperiod or excess dose of thyroxine (T4), followed by a reduction in egg production rate. The forced molting technique is used to avoid replacing pullets every year, although during the molting the rate of egg production is nearly zero. It has been proposed that changes in various endocrine functions are involved in both spontaneous and forced molting (1–9).
KeywordsProgesterone Level Short Photoperiod Excess Dose Gonadal Function Domestic Fowl
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