高水分苜蓿干草捆防霉复合添加剂配方筛选

为有效保存高品质苜蓿干草探索一种新型防霉复合添加剂,该试验选择5个主要防霉及载体成分,每个成分设置4个不同浓度水平,利用正交试验设计L16(45)进行防霉复合添加剂配方优化方案筛选。结果表明,硫酸钠和钠基膨润土为影响干草保存品质的2个主要影响因子;硫酸钾对提高干物质(dry matter,DM)和可溶性糖(water soluble carbohydrate,WSC),降低中洗纤维(neutral detergent fiber,NDF)和酸洗纤维(acid detergent fiber,ADF)效果最好;钠基膨润土明显改善了干草中粗蛋白(crude protein,CP)质量分数,是干草中CP、非蛋白氮(non-protein nitrogen,NPN)、灰分Ash含量的主要影响因子;而亚硫酸钾和a-淀粉酶对干草品质的改善作用相对次之;正交表试验设计结果分析表明,优化复合添加剂最优组合为硫酸钠35.51%,亚硫酸钾32.78%,硫酸钾1.64%,a-淀粉酶0.03%,钠基膨润土21.85%,葡萄糖8.19%。其添加后能够维持或提高高水分苜蓿干草贮藏后的干物质、粗蛋白、可溶性糖和灰分的含量,同时能够降低干草中中性洗涤纤维和非蛋白氮的含量。该组合添加剂在干草中的添加量为每吨干草添加1.15kg,应用成本为每吨干草11.5元。

Screening of compound additive formula for improving quality of high moisture alfalfa hay

The study was conducted to screen the optimum formula of compound additive used for obtaining high quality alfalfa hay with high moisture by using orthogonal experimental design (L16(45) with 5 factors and 4 levels for each factor. The moisture of alfalfa hay at bundling was 72% to 73%. Five components (factors) of Na2SO4, K2SO3, K2SO4, a-amylase, and sodium bentonite were used in this study. The application levels for Na2SO4 were 6, 9, 13, and 18 g/25 kg hay; K2SO3 were 1, 4, 8, and 12 g/25 kg hay; K2SO4 were 0.2, 0.6, 1.2, and 1.6 g/25 kg hay; a-amylase were 0.01, 0.05, 1, and 1.5 g/25 kg hay; and sodium bentonite were 2, 4, 8 and 12 g/25 kg hay. In addition, in order to improve the palatability of alfalfa hay, 3g/25 kg forage of glucose was added into each compound additive treatment. All the components were applied according to the schedule of the orthogonal experimental design at baling stage of alfalfa hay, and the bales were stored for 60 d. After storage, forage samples were obtained from each treatment and used for the analysis of the effects of each component and their combination on the stored forage quality. The results showed that Na2SO4 and sodium bentonite were the two major factors influencing the quality of stored alfalfa hay; Na2SO4 could influence most chemical components of alfalfa hay, such as water soluble carbohydrate (WSC), neutral detergent fiber (NDF), acid detergent fiber (ADF) and non-protein N; K2SO4 played an important role in improving forage dry matter (DM), WSC, NDF and ADF; whereas, K2SO3 and a-amylase were not as good as K2SO4 in improving the quality of alfalfa hay. Sodium bentonite could improve the crude protein content in alfalfa hay and was the major factor that affected the contents of crude protein, non-protein N and ash in alfalfa hay. Based on the analysis of results from orthogonal experimental design, the optimum additive formula was comprised by 35.51% Na2SO4, 32.78% K2SO3, 1.64% K2SO4, 0.03% a-amylase, 21.85% sodium bentonite, and 8.19% glucose. Application of this compound additive at bundling of alfalfa hay with high moisture could maintain or increase the DM, CP, WSC and ash contents of the hay; and decrease the NDF, ADF and non-protein N in alfalfa hay after 60 d of storage. The application rate of this kind of compound additive was suggested to be 1.5 kg per ton of hay, and it will cost 10 to 15 RMB per ton of hay.