裹包密度和添加剂对天然牧草青贮品质的影响研究

The Effects of Packaging Density and Additives on Silage Quality of Natural Pasture Herbage

以草甸草原牧草为试验原料,设置9个处理(每个处理3次重复),分别是LLAB(低密度,乳酸菌2.2×10^5cfu/g)、LCE(低密度,纤维素酶0.2g/kg)、LCK(低密度,无添加,CK),MLAB(中密度,乳酸菌2.2×10^5cfu/g)、MCE(中密度,纤维素酶0.2g/kg)、MCK(中密度,无添加,CK),HLAB(高密度,乳酸菌2.2×10^5cfu/g)、HCE(高密度,纤维素酶0.2g/kg)、HCK(高密度,无添加,CK)。60d青贮后开袋测定天然牧草营养品质、发酵品质和微生物数量。结果显示,天然牧草青贮中添加乳酸菌和纤维素酶,可以增加乳酸菌数量、乳酸含量和可溶性碳水化合物含量,提高牧草营养品质,降低纤维类物质含量和pH值。裹包密度较高时,营养品质和发酵品质越好。因此,添加乳酸菌和纤维素酶及高密度裹包有利于改善天然牧草青贮品质,且乳酸菌添加剂效果优于纤维素酶,高密度裹包优于低密度裹包。添加乳酸菌和高密度裹包可获得较好的天然牧草青贮饲料,可在草原牧区进行推广示范。

The natural pasture in meadow steppe was selected as research materials in this study, in which 9 treatments were set up(three replicates for each treatment): LLAB(low density, lactic acid bacteria 2.2×10^5cfu/g), LCE(low density, cellulase 0.2 g/kg), LCK(low density, no addition, CK), MLAB(moderate density, lactic acid bacteria 2.2×10^5cfu/g), MCE(moderate density, cellulase 0.2 g/kg), MCK(moderate density, no addition, CK), HLAB(high density, lactic acid bacteria 2.2×10^5cfu/g), HCE(high density, cellulase 0.2 g/kg) and HCK(high density, no addition, CK). After 60 days of silage, herbage packages were opened to determine nutritional and silage qualities, and microbial quantity of natural herbage. The results showed that adding lactic acid bacteria and cellulose enzyme can effectively increase contents of lactic acid bacteria and lactic acid, improve the stock of forage grass nutritional qualities, elevate the utilization rate of soluble carbohydrates, and reduce the fiber content and pH value. The higher packaging density was formed, the better nutritional and fermentation qualities would be. Therefore, lactic acid bacteria and cellulose enzyme addition combined with high-density packaging method were beneficial to improve the quality of natural grass silage, in which the effect of lactic acid bacteria additive was better than that of cellulose enzyme, and the effect of high-density packaging was better than that of low density packaging. It can be concluded that lactic acid bacteria addition and high-density packaging method can be applied to obtain better quality of natural pasture silage, which can be generalized in grazing areas.