Enhanced in vitro fermentation parameters of guinea grass ecotype ‘A’ (Panicum maximum) and rice straw (Oryza sativa) with supplementation of exogenous fibrolytic enzymes

摘要

Astudywasconductedtoevaluatetheuseofexogenousenzymesasapotentialmeansofimprovingtherumenfermentationofguineagrassecotype#8216;A#8217;(Panicummaximum)ricestraw(Oryzasativa).TheenzymesusedfortheinvitroincubationswerecharacterizedforCellulase(CE),Xylanase(XY).Enzymesweresupplementedseparately(CEandXY)aslevelsofenzymesin5,10,20,40and0μlfor500mgground(1mm)substratesdrymatter.Anaerobicbuffermediumandstrainedruminalfluid(42ml)wereaddedtotheinvitroincubations(followedby24hpreincubationofsubstrateandenzyme)intriplicatesandinvitrogasproduction(IVGP)wasmeasuredat2,4,8,12,18,24and48hofincubation.Attheendofincubationinvitrorumendrymatterdisappearance(IVRDMD),ammonianitrogen(NH3-N),shortchainfattyacid(SCFA)andmetabolozableenergy(ME)wereestimated.Allenzymetreatmentsexceptforsomeinstancessignificantlyincreased(p0.05)IVGPwhiletherewasnosignificanteffectonIVRDMDirrespectiveofenzymeorsubstrate.ThetotalNH3-Ninfermentationliquidwassignificantlyincreasedbybothenzymesirrespectiveofsubstrate.CalculatedvaluesforSCFAandMEalsohavesignificantlyenhancedwithenzymesupplementation.Thereforeitcanbeconcludedthattheuseoffibrolyticenzymesasaneffectivewaytoimprovetheruminalfermentationcharacteristicsofguineagrassecotype#8216;A#8217;andricestraw.