Dhofari cattle growth curve prediction by different non-linear model functions

摘要

Dhofaricattlegrowthcurvewasestimatedandfittedusingnon-linearfunctionmodelsofGompertz,VonBertalanffyandLogistic.Dataof2540weightperformancesof617Dhofaricattlefrombirthto228monthsofagewereusedinthisstudy.Analysisrevealedaninitialaveragelivebirthweightof17.8±0.99kgandof360±23.6kgatanaverageageof228months.TheestimatedvaluesofA(maturebodyweight)parameterrangedfrom316to321kgatagesrangedfrom36to48months.Parametersofbandkwereestimatedtobe2.11±0.021and,0.106±0.002,0.522±0.004and,0.087±0.001,and20.5±0.001and,0.127±0.002,forGompertz,VonBertalanffy,andLogisticmodelsrespectively.Inflectionweightsandtimewerefoundtorangefrom95to158kg,and5to9monthsofagerespectively.Degreeofmaturity(Ut)atbirthwas5.59,8.99,12.8%,andatpubertywas36.8,26.6,and44.0%forGompertz,VonBertalanffy,andLogistic,respectively.Modelsusedtofitthegrowthcurvehadhighdeterminationcoefficientsabove92%withthehighestwasforVonBertalanffy(93.6%)forgoodnessoffit.