Digestibility of dried and ensiled sweet potato roots and vines and their effect on the performance and economic efficiency of F1 crossbred fattening pigs

摘要

Twoexperimentswerecarriedouttoevaluatethedigestibilityofsweetpotatovine(SPV)androot(SPR)silageandmeal,andtodeterminetheeffectsonperformanceofincludingamixtureofSPVandSPRinbothensiledanddriedformindietsforF1crossbredfatteningpigs(MongcaisowxYorkshireboar).Thedigestibilitytrial(on-station)wasdoneaccordingtoa3*3LatinSquaredesignwith3treatmentson3castratedF1crossbredfatteningpigswithaninitialmeanliveweightof35kg.TreatmentSP0wasabasaldietwithoutsweetpotato,andwasreplacedbysweetpotatomeal(SPM)orsweetpotatosilage(SPS)atalevelof50%(DMbasis)togivetreatmentsSPM50andSPS50.Thefeedingtrial(on-farm)wasconductedwithatotalof40F1crossbredpigs(20femalesand20males)of15kgaverageinitialliveweightat4farmsasreplicates.Ateachfarm,10pigswerekeptin5pens(1maleand1femaleineachpen),witheachpenrepresentingatreatment.Thepigswerefeddietsconsistingofmixturesofthebasaldiet(SP0)andtheSPMorSPS(40%or60%SPM,and40%or60%SPS)togivetreatmentsSP0,SPM40,SPM60,SPS40andSPS60,respectively.TheSPMandSPSinbothexperimentsweremixturesof50%SPVand50%SPR(DMbasis).ThedigestibilityofDM,CP,CFandNDFinbothSPM50andSPS50dietswasabout90,77,92and89%,respectively,ofthevaluesrecordedfortreatmentSP0.Therewerenodifferencesduetomethodofprocessingthesweetpotatoes.Pigsonthecontroldiet(SP0)performedbetterthanonallothertreatmentsasregardsaveragedailygainandfeedconversionratio.nbsp;DietsSPM40andSPM60resultedinhigheraveragedailygainandbetterfeedconversionratiocomparedtodietsSPM60andSPS60.Therewerenodifferencesbetweennbsp;SPM40andSPS40.Thebackfatthicknessofthepigsrangedfrom1.99to2.28cmandwascloselycorrelatedwithfinalliveweightandrateofliveweightgain.nbsp;ThelabourcostforprocessingwashigherforSPMthanforSPS.