Effects of High Dose Copper Addition to Feed of Laying Hens on Egg Production, Egg-Shell Vv'eight and Egg-Shell Thickness

The aim of ıhc study was to assess the cffccl of dietary copper on cgg production and egg-shell qualtty. İn this study. 60 White Leghorn hens, 20 weeks of age. werc used. The hens dİvided inio two experimenial groupS and onc control group. Each groupS ineluded 20 hens. Experimental groups received certain copper addition in their feed. whcn the control group was given no cxtra copper in thcir feed. The colleeted eggs wcre analysed in terms of thcir shell ıhicknesse s and shell \veighıs. parametrically. During the first 42 days (early seven wceks) of the e.\periment. no significant difference has been observed about the cgg yields in bctwcCT ıhesc threc groups. But later. e\perimcnl-l group yielded more eggs than did oiher two groups (p<0.05>. VVhile the control group showed thicker cgg shells through the early periods {The first foilf period). fot the lası threc periods, the egg-shcll \veights from the same group proved to have been heavier than ıhose from both experimcntal groups. as observed in ıhis sıudy of 70 days of a duration. As conclıısion, it can be suggesicd that the high-dose copper in diets of laying hens has resulted in negaine effects on egg quality. But 250 mg/kg C u in diets effects on egg production positively.