添加乳酸菌和米糠对水稻秸秆青贮品质的影响

Effects of Adding Lactic Acid Bacteria and Rice Bran on the Fermentation Quality of Rice Straw Silage

为探讨水稻秸秆饲料化的可行性,以中粳水稻秸秆为青贮原料,研究了添加乳酸菌和米糠对水稻秸秆青贮料品质的影响。将新鲜稻草切碎后加入添加物,设乳酸菌组、米糠组、乳酸菌+米糠组,乳酸菌添加量为1 kg鲜稻草中加入0.02 g 1.6×105CFU/g乳酸菌制剂,米糠添加量为1 kg鲜稻草中加入100 g米糠,同时设对照组(无添加物)。原料装入聚乙烯袋青贮,45 d后开袋检测。结果表明,与对照相比,乳酸菌组稻草青贮料的可溶性碳水化合物含量、干物质回收率、乳酸含量和乳酸/乙酸值分别提高了60.63%、3.82%、134.78%和332.64%,挥发性脂肪酸含量、氨态氮/总氮值分别降低了53.74%、36.68%,且差异均达显著水平(P<0.05);米糠组稻草青贮料的可溶性碳水化合物含量、干物质回收率、乳酸含量和乳酸/乙酸值较对照组分别提高了31.06%、17.08%、157.10%和349.31%,挥发性脂肪酸含量、氨态氮/总氮值分别降低了44.90%、46.68%,且与对照差异均达显著水平(P<0.05)。乳酸菌+米糠组的青贮料发酵品质最佳,除酸性洗涤纤维含量与对照差异不显著(P>0.05)外,其他指标均显著优于对照(P<0.05)。pH与挥发性脂肪酸含量呈较强的正相关性,而与乳酸含量和氨态氮/总氮值呈较强的负相关性。综合各测定指标结果表明,同时添加乳酸菌和米糠能更好地改善稻草青贮料品质。

To discuss the feasibility of straw used as feed,the effects of lactic acid bacteria and rice bran addition on quality of medium japonica rice straw silage were studied.Four experimental groups were added respectively with lactic acid bacteria,rice bran,lactic acid bacteria ＋ rice bran,and no additives as blank control.Addition standard of lactic acid（1.6×105 CFU/g） bacteria preparations and rice bran were 0.02 and 100 g in 1 kg fresh cut rice straw,respectively.All materials were detected after ensiling for 45 d in polyethylene bags.The results showed that,in adding lactic acid bacteria group,water soluble carbohydrates（WSC） content,dry matter recovery（DMR）,lactic acid（LA） content and lactic acid/acetic acid（LA/AA） value were increased by 59.34.34%,3.82%,34.78% and 332.64%,while volatile fatty acids（VFAs） content and ammonia nitrogen/total nitrogen（AN/TN） value were decreased by 53.74% and 36.68%,compared with the control.The differences of above indexes between the two groups were all significant（P0.05）.In adding rice bran group,the WSC content,DMR,LA content and LA/AA value were increased by 26.52%,17.08%,157.10% and 349.31%,while VFAs content and AN/TN value were decreased by 44.90% and 46.68%.The differences of these indexes between the two groups were significant（P0.05）.Silage quality of adding lactic acid bacteria ＋ rice bran group was the best among the four groups,and all indexes were significantly better than those of control（P0.05）,except for acid detergent fiber content.There had been positive correlation between pH and VFAs,but negative correlation between pH and LA or AN/TN.It was indicated that the combination application of lactic acid bacteria and rice bran had better effect on fermentation quality of rice straw.