接种产阿魏酸酯酶罗伊氏乳杆菌对苜蓿裹包青贮发酵、抗氧化及消化率的影响OA

This study investigated the effects of inoculation with feruloyl esterase-producing lactic acid bacteria Lactobacillus reuteri A4-2 on the fermentation quality,antioxidant status,and in vitro digestibility of baled alfalfa silage.Chopped fresh alfalfa(Medicago sativa L.)at the early to full-blossom flowering stage was ran-domly divided into three groups:CON(without inoculant),YM13(inoculated with non-feruloyl esterase-pro-ducing L.reuteri YM13),and A4-2(inoculated with L.reuteri A4-2).Samples were collected after 20,40,and 60 d of ensiling to determine fermentation characteristics,free ferulic acid content,antioxidant enzyme activities,chemical composition,and in vitro dry matter digestibility.Compared with the CON and YM13,inoculation with L.reuteri A4-2 significantly reduced pH but increased lactic and acetic acid contents(P<0.05).Both inoculating L.reuteri YM13 and L.reuteri A4-2 in silage showed a higher dry matter content and lower ammonia nitrogen/total nitrogen than CON(P<0.05).Inoculation with L.reuteri A4-2 in alfalfa silage markedly enhanced the levels of free ferulic acid,superoxide dismutase(SOD),catalase(CAT),glutathione peroxidase(GPX)activities,and total antioxidant capacity(T-AOC)(P<0.05)relative to CON and YM13 during ensiling.In addition,inoculation with L.reuteri A4-2 effectively decreased neutral detergent fiber(NDF)and acid detergent fiber(ADF)contents,thereby improving in vitro DM digestibility compared with the other treatments(P<0.05).Overall,inoculation with L.reuteri A4-2 not only improved the fermentation quality of silage,but also enhanced the antioxidant capacity,reduced its fiber content,and improved its in vitro DM digestibility compared with the CON and YM13 groups,demonstrating significant application advantages.