Effect of various chemical treated-rice straws on rumen fermentation characteristic using in vitro gas production technique

摘要

Thisstudywasconductedtoinvestigatetheeffectofvariouschemicaltreatmentsofricestraw(RS)withurea,lime,sodiumhydroxideortheircombinationsonpotentialgasproductionandrumenfermentationcharacteristicsusingrumenfluidfromswampbuffalo(Bubalusbubalis).EnsiledRSwerecollectedafter14dofensiling,evaluatedforchemicalcompositionsandwereusedininvitrogasfermentationtechnique.nbsp;Itwasfoundthat,chemicaltreatmentsofRSshowedhighergasproduction(GP)thanthoseintheuntreatedRS.Particularly,GPwashighestfor5%ureatreatedRS(5UTS),followedby3.5%urea-limetreatedRS(3.5ULTS)and3%urea-treatedRS(3UTS).Before24hoursofincubation,therateofgasproductionwashighestin2%sodiumhydroxidetreated-ricestraw(2STS),butafter24hoursofincubation,itwassignificantlyreducedascomparedwiththe5UTS,3.5ULTSand3UTS.Ammonia-nitrogen(NH3-N)wasincreasedasaconsequenceofincreasingurealeveloftreatments.Totalvolatilefattyacid(VFA),acetateandpropionateconcentrationswerehigherforthe5UTSand3.5ULTSascomparedwithothertreatments(P0.05)whilebutyrateshowedhighestinsodiumhydroxidetreated-ricestraw(P0.05).InvitrodrymatterdigestibilityandmicrobialbiomassinthetreatedRSwerehigherthanthoseofuntreatedRS.nbsp;nbsp;Thisexperimentrevealedthatcombinationofureaandlimeat2%or3.5%treatmentofricestrawresultedinhighgasfermentationandwithsatisfactoryconcentrationofVFA.Furthermore,itcouldreducethetreatmentcostandismoresuitableforusebysmallholderfarmersinreducingthe5%urea-treatedricestraw.nbsp;