Models for gas production adjustment in ruminant diets containing crude glycerol

摘要

Theobjectiveofthisstudywastoidentifythemodel(Exponential,France,Gompertz,LogisticandDual-poollogisticmodels)thatbestfitsthecumulativegasproductioncurveinruminantdietsconsistedofthesubstitutionofmaizewithcrudeglycerol(0,4,8and12%).Alfalfahay(Medicagosativa)wasusedasroughageandcomprised60%ofthediet.Thecriteriausedwerethegraphicanalysisoftheobservedandestimatedcurves,graphicanalysisofresidues,meansquareerror,coefficientofdetermination(r2),residualmeanabsolutedeviation(RMAD),meanpercentageerrorandrelativeefficiency.Dual-poollogistic,Gompertzandlogisticmodelsshowedthehighestr2values,aswellasthelowestmeansquarederror.TheFranceandGompertzmodelshadthelowestmeanpercentageerror.Thedual-poollogisticmodelshowedthelowestRMADandrelativeefficiencygreaterthan1.0inallcomparisons,andtherefore,wasconsideredthemostefficientofthemodelsevaluated.