Dual purpose buffalo production in Colombia: lactation curve and weight of calves

摘要

Theaimofthisstudywastodescribethelactationcurve(LC),milkyieldat240(MY240),270days(MY270),theequivalentofbuffalomilktocowmilk(CME),lactationlength(LL)andweaningweight(WW)ofcalvesinColombianbuffaloindual-purposesystems.Recordsfrom359,718testdayfrom17,444deliveriesfrom5,691damsfrom17farmsand19,643calvesweaningweightsfrom8227damsfrom4farmswithdual-purposesystemwereused.GeneralizedadditivemixmodelswereusedtoestimateLCwithcontemporarygroupandlactationlengthsmoothnessasfixedeffectsforeachnumberofcalvinganddamasrandomeffect.FixedeffectsforWWwerecontemporarygroup,gender,damcalvingnumber;weaningageascovariableanddamasrandomeffect.GeneralizedadditivemodelwithPoissonfamilywasusedforLL,withdamcalvingnumberandcontemporarygroupasfixedeffectsanddamasrandomeffect.MY240andMY270werecalculatedwithLCsmoothnesscoefficientsandforCMEweretakenintoaccountMY270andWW.Fixedeffectsincludedinmodelsweresignificant(P0.05).Betweenthefirstandtwelfthcalving,meansrangedbetween4.1and4.7kg(lactationpeak),903and919kg(MY240),986and919kg(MY270),1653and1694kg(CME),238and250days(LL)and187and204kg(WW).Inconclusion,thelactationcurveissimilartodairycattle,wherethepeakoflactationoccursbefore50days.TheCMEisgreaterthan1300kg,acceptablevalueforproductionsystemsgrazingwithoutsupplementationandinderadverseagroecologicalconditions.