MECHANISMS OF AND METABOLIC REQUIREMENTS FOR COMPLETE AND RAPID REPRODUCTIVE REJUVENATION DURING AN INDUCED MOLT - A BRIEF REVIEW

Fasting to initiate reproductive involution ans body weight loss has been commonly employed for commercial induced molt procedures involving the Domestic Fowl Gallus domesticus. This mimics the anorexia associated with natural molt in some wild avian species. A body weight loss of approximately 30% was found to produce optimum postmolt reproductive performance with regard to rate of egg production and eggshell quality. Lipid in the shell gland was found to be reduced only after a body weight loss of 25% was achieved. Others have reported an induced molt to be associated with an increase in the shell gland phosphatidylcholine to phosphatidylethanolamine ratio and an increase in tissue accumulation of calcitriol. We have reported an increased concentration and activity ot shell gland calcitriol receptor as well as an increase in calbindin-D28k. These results suggest that complete involution of the oviduct and shell gland is necessary for complete restructuring and rejuvenation. There was evidence that a high protein diet during recrudescence aids in the rapid return to reproductive function.