Elsevier期刊投稿英文模板(Animal-Feed-Science-and-Technology).docx

63646566676869707172737475767778798081828384851IntroductionItiswidelyacceptedthatdair>fcowshaverequirementsforaminoacids(AA)thatmustbeprovidedinthedietasasupplementIoIheAAin11icrobialproteinthatpassesfromtheru11>en.HoweverduetothelackofcommercialavailabilityofruminalIyprotected(RP)Iysincthatescapestheforestonachundigestedktherebymakingitavailableforabsorptioninthesmallinlesline,thereisIildcexperimentaldataIosupportproductivebenefitstosupplementationofdairyrationswithlysine.Previousresearchers(Velleetal.1997.1998:Voldenetal.1998)havereportedruminalescapeofIysincIhalvariedfromabout100to291g/kgofthelysinedosed,dependenluponthelevelofIysincdosedtotherumen.Suchlevels,particularlythehigherones,maketheuseoffreelysineapotentiallyeconomicalsourceofintestinallyavailablelysine.However,the11>elh<lofadminisl11lionoflysineinallthreeofthesestudies,asapulsedose,mayhaveresultedinarelativelyhighestimateofruminalIysincescapeduetotransitorilyhighconcentrationsoflysineinrumenfluid,whichthenwashedoutoftherumenathighlevelsduetothehighpassage11lesofrumenliquids.Theobjectiveofthisstudywastofeedcowsunprotected1.-IysincHCI.atlevelssimilartoVoldenetal.(1998).butmixedintothediet,inordertoestimateruminallysineescapeunderconditionssimilartothoseusedincommercialsituations.HoweverotherobjectivesweretodetermineiffeedingfreeIysincimpactedrumenfermentationandfunction,frcstomachNDFdigestion,forestomachescapeofmicrobialbiomass,andproductivityofthecows.Thisstudy(iiITeredfromRobinsonetal.(2005)onlyinthatthecowswerenotthesameandthecorngrainfedwasfinegroundasopposedtocoarsecracked.Howeverasecondstudywasdeemedtobeworthwhileinordertoincreaseconfidenceinalltheresultsobtained.2.MaterialsandmethodsThestudywascompletedsimultaneouswithRobinsonetal.(2005)andsoonlyabriefsummaryofthematerialsandmethodsarePreSCnledhere.2. 1.CoyvsandDesignFivemultiparousHolstcincows,duetoealvewithina4weekperiod,werefittedwithlargediameterrumencannulae(BarDialnond.Parma.ID,USA)l>etween6and8weekspriortotheirpr<yeciedcalvingdale.DuringIhebalanceoftheirdryperi<xis,Ihecowswerefedaherdbasedrycowration.Atcalving,allcowswerechangedtothepostpartumherdbasetotalmixedration(TMR)untiltheirassignmenttotreatment.AstherewerenohealthorcalvingProbIeInSwithanycow,thecowwihthelowestmilkyieldwasdropped.Cowswerehousedinliestalls,beddedwithsoftwoodshavingsonrubbermatsandprovidedfreeaccesstowater.Cowswereassignedtoa4x41.atinsquaredesignbetween2and4weekspost-arun.AllcowswereledthesameTMR(Table2),andIreatnwntdiClerenceswereachievedbymanuallyincorporating1.-IysincHClintoeachcow,sindividuallyweighedallocationofTMRatfeeding.TheTMRwasfedat07:(X)h(333g/kgofdailyallocation)and14:00h(667g/kgofdailyallocation)andthe1.-IysineHCIwasallocatedinIhesameProPOrIiOnSIcIhCindividualfeedings.Treatmentsweredesignedtodeliver0.I,2or3gof1.-Iysincfrom1.-IysincHCI(AjinomotoIw.,Tokyo.Ja>an)perkgofDMintakebut.duetothemethodofestimatingexpectedfutureDMintake,actualvalueswereabout16%higher.ActuallysinedeliverylevelsarcinTable3.868788899091%93949596979899I(X)IOI102103KM1051062.2. Measurementsandanalyficalmethods107108i(»IIO111112IB114115116117HS119120121122123124125126127128SilagesandTMRwereprocured,sampledandassayedaspreviouslydescribed(Robinsonelal.2005).Ortsweresampledondays15.17and20ofeachperiodandcompositedwithincowandperiodrelative(otheweightssampled.Cowsweremilked,amimilksampledamiassayed,aspreviouslydescribed(Robinsonetal.,2005).aswerebodyweights(BW)andb<xlyconditionscores(BCS),whichwerecollectedatthebeginningofeachexperimentalperiodandattheendofIheexperiment.Apulsedoseof35gofCoEDTA4preparedasdescribedbyUdcnclal.(I98wasdissolvedin200mlofwaterandmanuallyinfusedtotherunwnthroughtherumencannulaat06:55h(i.e.,immediatelybeforefeeding)onday19ofeachexperimentalperiod.Rumenfluidwassampledat06:50h(i.e.,immediatelyprior(oCoEDTAinfusion),07:00,07:30,08:30,09:30,11:00.12:30and14:00honday19ofeachperiod.Sampling,samplepreservationandanalyticalproceduresforlysine,CoammoniaN.totalNandVFAwereasdescribedbyRobinsonelal.(2(X)5).Samplesofrmenfluidwerealsocollectedat()9:00and13:00honday20ofeachperiodandruminalIxicteriawereisolated,preservedandassayedasdescribedbyRobinsonetal.(2005).SamplesofwholerumeningestawereCOIICCICdat09:00andI3:(X)honday21ofeachperiod.Sampleswerecollected,preservedandassayedaspreviouslydescribed(Robinsonetal.25).2.3. CalculationsRumenliquidturnoverratewascalculatedasthedeclineofthenatu11llogarithmoftheCoconcentrationduring(heAMfeedingperiod,andtherumenliquidvolumewasestimatedastheCodoseinfusedat06:55hdividedbytheextrapolatedCoconcentrationatr=0.129130131132133134135136137138139140141142143144145146147148149150151Estimatedruminalnon-diges(ionofNDFwasdeterminedastheIignin/NDFral100fIherumeningestadividedbythelignin/NDFrat100ftheTMRfed.butassuming50g/kgdigestion(i.e.disappearance)oflignininIherumen(