Effects of duckweed on the laying performance of local (Tau Vang) hens

摘要

Eightylocal(TauVang)layinghensat19weeksofagewereallocatedto5dietarytreatmentsand3replicates.Thecontroldietwasamixtureofbrokenriceandroastedsoyabeans(SB100)withnoduckweednbsp;nbsp;Fortheotherfourdietsduckweedwasavailableadlibitum,giving5treatmentswithnbsp;roastedsoyabeansatlevelsof0,25,50,75and100%(SB0DW,SB25DW,SB50DW,SB75DWandSB100respectively).IntakesoffeedDMandconcentrateDMwerenotdifferentamongtreatments.Intakeofduckweedincreasedasthenbsp;roastedsoyabeanscontentoftheconcentratedietwasreduced,contributingupto29%ofthetotaldietaryproteinonthezerosoyabeanbasalfeed.Thecrudeproteincontentofthetotaldietdeclinedlinearly(from16.8to12.5%inDM)asthenbsp;roastedsoyabeansproteincontributionwasreducedfrom100to0%.Ageatfirsteggdecreasedinacurvilinearresponsetotheproportionofdietaryproteincontributedasduckweed,withoptimumvaluesaroundthe75%replacementlevel.nbsp;Eggsproducedperlayerinthe56dayperiodwerelinearlyrelatedwithpercentproteinfromduckweed.Therewasnoconsistenttrendforfeedconversionintoeggs.Averageeggweightandtheproportionoftotaleggsweighingover38gtendedtoshowacurvilinearresponsetotheproportionofproteinderivedfromduckweedwithoptimumvaluesataround20%asduckweedprotein.nbsp;Bothfertilityofincubatedeggsandhatchabilityoffertileeggsshowedcurvilinearrelationshipswithproportionofproteinderivedfromduckweed,withoptimumvaluesataround15%andnbsp;25%asduckweedproteinforfertilityandhatchability,respectively.Theyolkpigmentationoftheeggsincreasedinresponsetoproteinderivedfromduckweed.TheyolkindexofeggsfromhensontheSB100dietwasslightlylower(0.38)thantherecommendedstandardof0.4.nbsp;nbsp;Highestnbsp;productionandbetterfertilityandnbsp;hatchabilityofeggsfromhensconsumingtheSB25DWdietresultedinhighestnumbersofchickshatchedandthehighestgrossincomeandmarginoverfeedcosts..Itisconcludedthateggproduction,eggquality,feedconversionandnetprofitarehighestwhenfreshduckweednbsp;replaces75%oftheproteinfromnbsp;roastedsoyabeansinadietbasedonbrokenrice.Evenat100%ofnbsp;roastedsoyabeansreplacementbyduckweed,nbsp;theeggproductionandmarginofincomeoverfeedcostswerebetterthanonthenbsp;controldietinwhichthesupplementaryproteincameonlyfromnbsp;roastedsoyabeans.