Using mixed models to describe growth in buffaloes

摘要

Theobjectiveofthisstudywastoevaluategrowthbetween12monthsandslaughterin123castratedmalebuffaloes.Bodyweightdata,ultrasound,andbovimetricmeasurementswereused.nbsp;Linearmixedmodelsoffirstandsecondorderwereused.Themodelincluded#8220;lot#8221;asafixedeffect.nbsp;#8220;Individual#8221;andthethreeparametersofthemodelwereincludedasrandomeffects.Thesecondordermodelhadthebestfit.#8220;Lot#8221;hadahighlysignificanteffect(p0.01)formostofthetraits.The#946;ovalues,estimatedforbodyweight(BW),Ribeyearea(REA),andrumpfatthickness(RFT),were184,20.3,and0.65,respectively.Monthlyincrements(#946;1)correspondedto28,44,3.72,1.25;anddeceleration(#946;2)was-0.61,-0.116,-0.011,respectively.Measurementsofheightatthesacrum(HS)andheightatthewithers(HC)agreedwithliteraturereportsforthisspecies.Chestcircumferencemeasurements(CC),bodylength(BL),separationbetweentheilia(II),anddistancebetweenilium-ischium(IIS)werelowerthanthosereportedintheliterature.Buffalogrowthwaswelldescribedbythequadraticmodel.Thismodelfitsbetterthegrowthcurveforbuffaloeswhenrandomparametersareincluded.Duringthestudy,animalsmaintainedthenormalphysiologicalbehaviordescribedforcattlegrowth.