Feed level and body condition score at calving effect on milk production in dual purpose cows Bos taurus x Bos indicus

摘要

Withtheaimtoevaluatefeedinglevelandbodyconditionstoreatcalveanexperimentwasdesignusing28crossbredcows(BostaurusxBosindicus)fromaexperimentalherdofFacultaddeAgronomíaofUCV,inVenezuela.Mainandinteractionseffectofhighandlowfeedinglevel(NA,NB)andbodyconditionscore(NIRD1-5)atcalving(high[#8805;2,5](CA)orlow[2,5](CB2.5)wereevaluatedbyrandomanalysisinfactorialarrangementwithrepeatedtimemeasurementsuntil45postpartumdays.DietsweredesignedbyNRCrequirements.Hay,multinutritionalblockandsupplementconsumption(kg/cow/d)weremeasureddailyforeachcowindividually.Saleablemilkandcalfmilkconsumption(estimatedbydoubleweightmethod,beforeandafter30minofrestrictedsucklingpostmorningmilking)weremeasured(kg/cow/d)dailyandtwiceperweekrespectively,andineachmilkfractionwasmeasuredfatcontent(%)twiceperweek.nbsp;At45daysofcalvingtherewasnoevidenceoftreatmenteffects.Itispossiblethatthecomplexmechanismofnutrientpartitioningandhighgeneticvariabilityrequiremoreprolongedstudies,withgeneticevaluationandchangesinphysiologicalinteractionsinordertoexplaintheresultsandthereforecontributetothedevelopmentofappropriatemanagementsystems.nbsp;