Evaluation of rations supplemented with fibrolytic enzyme on dairy cows performance. In situ ruminal degradability of different feedstuffs

摘要

ThisexperimentwasconductedtostudytheeffectoffibrolyticenzymessupplementationoninsitudegradabilityofDM,CPandCFofdifferentfeedstuffsincludedconcentratefeedmixture(CFM),berseemhay(BH),driedsugarbeettops(DSBT),cornsilage(CS),ricestraw(RS)andwheatstraw(WS).Thefibrolyticenzyme(fibrozyme)wasaddedtothegroundfeedstuffsatthelevelsof0,1and1.5g/kgDMdilutedwithdistilledwater(1:10w/v)andsprayedwith10mlperkgofgroundfeedstuffsovernightandsamplesincubatedincanulatedmultiparousFriesiancowsfor2,4,8,16,24,48and72hours.ConcentratefeedmixtureshowedthehighestvaluesofDM,CPandCFdisappearancefollowedbyDSBT,whilebothRSandWShadthelowestvalues(P0.05).Moreover,theaddedfibrozymeatthelevelof1g/kgshowedthehighestinsituruminalDMandCFdisappearanceforCFMandDSBTandCPdisappearanceforCFM,BHandDSBT,whilethelevelof1.5g/kgrecordedthehighestDMandCFdisappearanceforBH,CS,RSandWSandCPdisappearanceforCS,RSandWS.TheDSBTshowedthehighestrapiddegradablefraction(a),CSthehighestpotentialdegradablefraction(b),CFMhadthehighestdegradationrate(c)andRSandWShadthehighestundegradablefraction(u)forbothDMandCP(P0.05).While,CFMshowedthehighestrapiddegradablefraction(a),CSrecordedthehighestpotentialdegradablefraction(b),CFMhadthehighestdegradationrate(c),butRSandWSshowedthehighestundegradablefraction(u)forCF(P0.05).Moreover,CFMshowedthehighestoutflowrateofdegradableDMat2,5and8%/hourfromtherumenforDM,CPandCF,butbothRSandWShadthelowestvalues.nbsp;Fibrozymeaddedatthelevelof1g/kgshowedthehighestinsituruminalDMandCFdegradationforCFMandDSBTandCPdegradationforCFM,BHandDSBT,whilethelevelof1.5g/kgrecordedthehighestDMandCFdegradationforBH,CS,RSandWSandCPdegradationforCS,RSandWS.