IMPACT OF FEED RESTRICTED SYSTEM AND ZINC FORMS ON SOME PRODUCTIVE PERFORMANCE TRAITS, EGG QUALITY PARAMETERS AND ECONOMIC EFFICIENCY OF MANDARAH LAYING HENS.

This study was conducted to determine the effect of feeding different level of restricted feed with different forms of zinc(Zn) on productive performance, egg quality traits and economic efficiency of Mandarah (Egyptian local developed strain) laying hens. A total number of 270 laying hens + 27 cocks, 24 weeks old were randomly taken to be similar in (1228.0 ±44.0 g) in the study. Birds were randomly divided into nine experimental groups,(30 hens + 3 cocks in each group) and each group was contained three replicates (10 hens+ 1 cock / replicate). The experimental groups involved a3x3factorial arrangement, 3 zinc forms (control, organic zinc and Nano-Zn) and 3 levels of restricted system groups (ad libitum, 90 % and 80 % / hen / day) were fed a balanced basal diet without supplemented zinc as a control or supplemented with 50 mg Nano zinc /Kg diet or 50 mg zinc from zinc methionine /Kg diet, respectively),during the experimental period lasted six month. The obtained results showed that laying hens fed ad libitum / hen /day and 50mg Nano-Zn/Kg diet recorded the highest (P<.01) for egg production( %), egg weight, egg mass, feed conversion / eggs and body weight compared with the control and other groups. Dietary Nano-Zn increased significantly total body weight change, egg production (%); egg mass and improve feed conversion / eggs, most of egg quality. Receiving 90% feed/ hen/day recorded the best of economic efficiency. The best value of net revenue and economic efficiency of laying feeding 90% hen / day and supplemented organic zinc. Conclusively, feeding restricted system at level of 90% and dietary 1018 WESAM IBRAHIM et .al recommended to improve productive performance traits, egg quality parameters and economic efficiency of Mandarah laying hens.