不同添加剂处理对苜蓿青贮品质的影响

摘要

研究探讨6种不同添加剂（甲酸、丙酸钙、双乙酸钠、葡萄糖、纤维素酶、乳酸菌接种剂）对苜蓿青贮的发酵品质及营养成分的影响。结果表明，添加甲酸可以改善苜蓿青贮的发酵品质，青贮pH显著下降（P＜0．05），乳酸含量增加（P＜0．05），氨氮含量减少（P＜0．05），粗蛋白、总糖和淀粉含量增加；丙酸钙组氨态氮和丁酸含量显著低于对照组（P＜0．05），乙酸和乳酸含量显著高于对照组（P＜0．05），粗蛋白、粗纤维及总糖等营养成分与对照相比变化不显著；添加双乙酸钠对青贮的营养成分及青贮品质影响不大；添加酶制剂组，pH显著下降（ P＜0．05），氨态氮含量显著高于对照组（P＜0．05），乙酸、丁酸和乳酸含量低于对照组但差异不显著，粗蛋白含量显著高于对照组（P＜0．05）；添加乳酸菌组，氨态氮及乳酸含量显著高于对照组（P＜0．05），粗纤维高于对照组，粗蛋白低于对照组；添加葡萄糖组，pH 显著下降（ P＜0．05），乳酸含量增加（P＜0．05），氨态氮及丁酸含量显著低于对照组（P＜0．05），干物质、粗蛋白及总糖含量低于对照组，水分、粗纤维、总能及淀粉的含量高于对照组，但差异不显著。在上述6种添加剂中，甲酸青贮效果最佳，发酵品质好、蛋白质损失小。%T he study w ere conducted to investigate the fermentation and nutrient variance of alfalfa si‐lage after using 6 additives of formic acid ,calcium propionate ,sodium diacetate ,glucose ,cellulose and lactic acid bacteria inoculation .The results showed that ,formic acid improved the fermentation quality of alfalfa silage ,silage pH decreased significantly (P<0 .05);lactic acid content increased (P<0 .05);am‐monia nitrogen content decreased (P<0 .05) ,the crude protein ,total sugar and starch content increased in general .Compared with the control group ,ammonia nitrogen and acid content in calcium propionate group were significantly lower (P<0 .05) ,acetic acid and lactic acid content were significantly higher (P<0 .05) ,nutritional components of crude protein ,crude fiber and total sugar displayed insignificant vari‐ance;The addition of sodium diacetate had little effect on silage nutrition composition and silage quality while addition of cellulose enzyme significantly decreased the pH value(P<0 .05) ,increased ammonia ni‐trogen content (P<0 .05) ,slightly decreased acetic acid ,butyric acid and lactic acid content ,and evident‐ly improved the crude protein content in comparison with those in control group (P<0 .05);In the group added lactic acid bacteria ,ammonia nitrogen and lactic acid content were higher than that of the control group (P<0 .05) ,crude fiber is higher and the crude protein lowe;Adding glucose significantly decreased pH (P<0 .05) ,increased lactic acid content (P<0 .05) ,and lowered ammonia nitrogen and butyric acid content (P<0 .05) ,decreased the dry matter ,crude protein and total sugar content ,and slight increased the content of moisture ,crude fiber and starch .In conclusion ,among the 6 kinds of additives ,silage add‐ed formic acid revealed the best fermentation quality and least loss of protein .