Performance of Prim' Holsteins and Montbéliardes dairy cows in North-East Algeria

摘要

TwobatchesofheifersimportedfromEurope,10ofracePrim'Holstein(PH)and10Montbéliardes(MB),ingestationof5,5±0,4(MB)and5,6±0,4months(PH),oldof26,5±0,9(MB)and18,6±0,9months(PH),withaweightof558±52kg(MB)and474±43kg(PH),werefollowedon3successivelactationsunderthesameconditionsofbreeding.The1stcalvinghasbeenat24,2±0,8monthswithaweightof510±45kgforracePHandwith32,1±0,8monthsand580±49kgforraceMB.Forthetworaces,theenergyassessmentwasalwaysnegativewiththe60dayoflactation.Theperformancescarriedoutarebelowpotentialitiesofdairyproductionandreproductionofthetworaces.TheywerebetterinraceMB:4211±340kg(MB)and3965±328(PH)inthe1stlactation,5024±360kg(MB)and4660±420(PHinthe2ndlactation,5700±530kg(MB)and5180±400(PH)in3rdlactation.Thestateofthebodyscorecondition(BSC)wasdegradedgraduallyduring3lactationstoreachlevelsbelow2pointsofBSC.Withdryingup,theMBalwaysreturnedonabetterlevelofreconstitutionofthereservescomparedtothePHwithoutneverreturningonthelevelasofreservestocalving.ThetimesoffertilitywerelongerattheracePrim'Holstein.ThenegativeeffectswerenotedatthePHcalvingforthefirsttimein24monthsthanattheMBcalvingin32months.Thus,theimportationoffullheifersmustbeobjectiveandmusttakeaccountoftherace,oftheagestotheintroductionandthefirstcalving,oftheconditionsoffeedingandthecontrolofthereproduction.