Abstract: Sorghum-Sudangrass hybrids were ensiled after treated with acetic acid (0.5%, AA),propionic acid (0.5%), propionic acid (0.5%) and urea (0.5%) mixture, snow LACT-JL (0.0005%, SL) and acremo conc.(0.0017%, AC). Fermentation qualities, chemical compositions and poly unsaturated fatty acids of silage were analyzed to determine additives contributing to Sorghum-Sudangrass hybrids silage. Results showed that Sorghum-Sudangrass hybrids silage without additives had 4.95 pH value and 16.85% ammonia nitrogen/total nitrogen ratio, which were not qualified with nutrition largely lost. However, pH value of silage was significantly reduced after adding AA, PA, PA+U, AC (P<0.05). All tested additives could significantly increase crude protein concentration and decrease ammonia nitrogen/total nitrogen ratio (P<0.05), then improve fermentation qualities and nutritional value of silage compared with control. All tested additives could significantly increase linoleic acid and linolenic acid concentration (P<0.05), in which AC had the most obvious effect on increasing linoleic acid and linolenic acid concentration.

Key words: Sorghum-Sudangrass hybrids, Additives, Silage, Silage quality

摘要： 以高丹草(Sorghum bicolor×Sorghum sudanense)为原料,分别添加乙酸(0.5%,AA)、丙酸(0.5%,PA)、丙酸(0.5%)+尿素(0.5%,U)混合试剂、乳酸菌菌剂snow LACT-JL(0.0005%,SL)及乳酸菌菌剂acremo conc.(0.0017%,AC)共5个处理调制青贮,分析发酵品质、营养成分和不饱和脂肪酸含量,以确定有利于高丹草青贮的添加剂。结果表明:高丹草单独青贮时pH值达4.95,氨态氮占全氮比例高达16.85%,营养物质损失大,青贮效果不理想。添加AA,PA,PA+U和乳酸菌菌剂AC后,高丹草青贮的pH值显著低于对照组(P<0.05),5种添加剂处理均能显著提高粗蛋白含量并降低氨态氮占全氮比例(P<0.05),可使高丹草青贮的发酵品质和营养价值得到改善。各处理中高丹草青贮料的亚麻酸含量均高于亚油酸含量,各添加剂均可显著提高亚麻酸和亚油酸含量(P<0.05),其中乳酸菌菌剂AC提高亚油酸和亚麻酸含量的效果最明显。

关键词: 高丹草, 添加剂, 青贮, 青贮品质