Effect of Dietary Vitamin E on the Performance, Plasma and Egg Yolk Vitamin E Levels and Lipid Oxidation of Egg in Heat Stressed Layers

摘要

ThisstudywasconductedtoinvestigatetheeffectsofdietaryvitaminElevelsontheconcentrationofvitaminEofeggyolkandplasma,TBARS(thiobarbituricacidreactivesubstance)ofeggyolkduringrefrigeratedstorageof1or42daysandproductiveperformanceoflayinghensexposedtoheatstress(30oC).Twentyfourweekold,128LohmanLSLhybridslayersdividedinto8groups.Halfofthegroupswerekeptatnormalpoultry-houseconditions(20oC)andtheotherhalfwereexposedtoheatstress(30oC).Inbothpoultry-houses,formergroupswerefedonbasaldietsand2nd,3rd,and4thgroupswerefedonthevitaminaddedrationswhichwere45,65,85IU/kgvitaminErespectively.SupplementationofvitaminEcausedaverysignificantincreaseintheeggyields.Eggproductionwassignificantlygreater(P0.01)with85IU/kgvitaminE(81%)ascomparedtocontrolhens.Ontheotherhandtheaverageeggyieldsweresignificantlydecreased(approximately14%)bytheheatstress.AhigherconcentrationofvitaminEreducedTBARSvaluesineggs.ConcentrationofvitaminEintheyolkandplasmalinearlyincreasedasthedietaryvitaminEincreased.