Mitigating methane production from ruminants; effect of supplementary sulphate and nitrate on methane production in an in vitro incubation using molasses and cassava leaf meal as substrate

摘要

Thisinvitroincubationwasarrangedasa2*3factorialinacompletelyrandomizedblockdesignwith6treatmentsand4repetitions.ThefirstfactorwasthesourceoffermentableN(potassiumnitrateorurea);thesecondfactorwasthelevelofaddedsulphur(0,0.4and0.8%ofsubstrateDM,assodiumsulphate.nbsp;Thesubstratewasmolassesandcassavaleafmeal.Incubationswerecarriedoutonsuccessivedaysfor6,12,18,24and48h.nbsp;Attheendofeachincubation,volumeofgasandnbsp;percentagemethanewererecorded,andtheresidualsubstratefilteredtodeterminetheamountofsubstratesolubilized.nbsp;Gasproduction,percentagemethaneinthegasandmethaneproductionnbsp;werereducedbyreplacingureabynitrateatincubationtimesfrom6to48h,andwereincreasedwithlengthofincubation.Addednbsp;sulphurnbsp;increasedmethaneemissionsinthepresenceofnitrateovertheearlyincubationperiodsindicatingagreaterfermentationrateinthatperiod,butsulphurwasadditiveindecreasingmethaneinlongerincubations,indicatingnitratehadbeenfullyreducedandsulphurreductioncommencedThereductioninmethaneproductionafter48hofincubation,whennbsp;sulphurandnitratewerecombined,wasgreaterthanwhennitratewasusedalone