The use of ensiled cassava leaves in diets for growing pigs. 1. The effect of graded levels of palm oil on N digestibility and N balance

摘要

FourMongCaixLargeWhitecastratemalepigsweighingonaverage9.6kgwereallotedatrandomintofourdietstostudytheeffectofgradedlevels(0,5,10and15%indrybasis)ofrefinedpalm(Elaeisguineensis,Jacq.)oilintroducedindietsofbrokenriceandensiledcassavaleavestostudynutrientdigestibilityandbalanceofNaccordingtoa4x4Latinsquaredesign.Thesilagewasmadefromsun-dried,wilted,choppedleavesofcassavanbsp;harvestedafter4.5to5monthsofgrowth.Thecassavaleaveswereensiledwith5%ofsugarpalm(Borassusflabellifer)syrupandstoredduring30daysinplasticcontainersof100kgcapacity.ThecharacteristicsofthesilagewerepH4.10,DM50.7%,ash14.1,organicmatter85.9,NDF47.0,crudefibre35.3,andN3.92%indrybasis,respectively.Thecyanidecontentofthesilagewas110mg/kgDM.Meanenvironmentaltemperaturewas35oCatmidday(12:00)duringthetrial(May2002).Observedfeedintakewasslightlylowerthanthatprogrammed(50gDM/kgbodyweight)andwasonaverage45.6gDM/kgbodyweight.Anonsignificantslightincreaseoffeedintakefrom88.4to92.2%fromthatprogrammedwasfoundwithincreasinglevelsofdietarypalmoil.Duringtheentiretrialthepigswereinapositivebodyweightbalanceandtherewerenosymptomsofanimaldiscomfort.Drymatterandorganicmatterdigestibilitiesweredecreasedasthelevelofdietaryrefinedpalmoilwasincreased.nbsp;Energydigestibilitywasnotsignificantlyinfluencedbygradedlevelsofpalmoilinthediet.nbsp;Incontrast,etherextractdigestibilityincreasedsignificantly(P0.001)withincreasedlevelsofrefinednbsp;palmoilinthediet.Thedigestibleenergycontentofthedietsincreasedfrom14.03to17.26MJ/kgDMwithincreasinglevelsofpalmoil.NeitherNdigestibilitynorNretentionwereaffectedbytheinclusionofrefinedpalmoilinthediet.Ndigestibilitywasrelativelylow(overalmean,66.7%)butNretentionasrelatedtoNdigestedwashigh(overallmean,82.7%).Itissuggestedthatifrefinedpalmoilisincludedinthedietupto15%oftheDM,therewillbenoadverseeffectonnutrientdigestibilityandNbalanceofpigsfeddietsbasedonhighlevelsofensiledcassavaleavesandbrokenrice.nbsp;