不同丙酸浓度对天然牧草青贮品质及有氧稳定性的影响

Effects of Different Propionic Acid Concentration on the Quality and Aerobic Stability of Natural Forage Silage

为改善天然牧草青贮品质,研究不同丙酸浓度对天然牧草青贮品质及有氧稳定性的影响,以确定天然牧草青贮丙酸最适添加量。试验以锡林浩特市毛登牧场天然打草场的牧草为原料,共设四个处理组,丙酸添加量分别为0 mL·kg^(-1)(CK,对照组),2mL·kg^(-1)(T1),4mL·kg^(-1)(T2),6mL·kg^(-1)(T3),在厌氧发酵60天后测定其营养品质、发酵品质、微生物数量及有氧稳定性。结果表明:与对照组比较,各丙酸浓度处理组均显著提高了可溶性碳水化合物(Water soluble carbohydrates,WSC)含量(P<0.05)、提高了粗蛋白质(Crude protein,CP)含量、显著降低了pH值(P<0.05)、显著提高了乳酸含量(P<0.05);各丙酸浓度处理组中乳酸菌含量均显著提高(P<0.05)、大肠杆菌含量均显著降低(P<0.05)、有氧稳定性均显著提高。说明添加丙酸可以改善天然牧草青贮品质且提高有氧稳定性,在丙酸添加量为2mL·kg^(-1)时即可达到较好效果。

In order to improve the quality of natural forage silage,the effects of different concentrations of propionic acid on the quality and aerobic stability of natural forage silage were studied to determine the optimal addition amount of propionic acid in natural forage silage.The natural forage grasses in Maodeng pasture of Xilinhaote City were used as materials in the experiment,and four treatment groups were set up based on the propionic acid addition including 0mL·kg^(-1)(CK,control group),2 mL·kg^(-1)(T1),4 mL·kg^(-1)(T2)and 6mL·kg^(-1)(T3).After 60days of anaerobic fermentation,the nutritional quality,fermentation quality,microbial quantity and aerobic stability were determined.The results showed that compared with the control group,the content of Water soluble carbohydrates(WSC)significantly increased(P<0.05),the content of Crude protein(CP)increased,the pH value significantly decreased(P<0.05),and the lactic acid content significantly increased(P<0.05)in any adding propionate treatment group.The content of lactic acid bacteria significantly increased(P<0.05),the content of Escherichia coli significantly decreased(P<0.05),and the aerobic stability significantly improved in any propionate concentration treatment group.The results showed that the addition of propionic acid could improve the quality and aerobic stability of natural forage silage,and the best effect was the addition of 2mL·kg^(-1) propionic acid.