Abstract:

In order to investigate the degradation rule of different varieties of alfalfa(Medicago sativa L.)in cattle rumen, this study was conducted to determine the rumen degradation rate and degradation parameters of ten different alfalfa varieties in rumen of three Jinnan cattles using the nylon bag technique, which included dry matter(DM), crude protein(CP), neutral detergent fiber (NDF) and acid detergent fiber (ADF). The results showed:DM, CP, NDF and ADF degradation rates of different varieties of alfalfa increased with the extension of incubation time, but the degradation rate of every variety showed significant difference within the same period; There were significant differences among the effective degradation rates (ED) of different varieties of alfalfa. DM effective degradability of ‘WL-319HQ’ had significant difference with ‘Zhongmu No.1’ and ‘Captain’ (P<0.01); CP effective degradability of ‘Queen’ was significantly higher than other varieties except for ‘Sidel’; NDF effective degradability of ‘WL-168HQ’ and ‘Zhongmu No.1’ had significant difference with other varieties except ‘Captain’; ADF effective degradability of ‘Sandili’ and ‘Queen’ had significant difference with others(P<0.05). So the ruminal degradation characteristics of different alfalfa varieties were different.

Key words: Alfalfa, The nylon bag technique, Ruminal degradability

摘要：

为研究不同紫花苜蓿（Medicago sativa L.）品种在牛瘤胃中的降解规律，本试验以10个紫花苜蓿品种为材料，以3头装有永久性瘘管的晋南牛作为试验动物，采用尼龙袋法测定不同紫花苜蓿品种干物质（DM）、粗蛋白质（CP）、中性洗涤纤维（NDF）和酸性洗涤纤维（ADF）的瘤胃降解率和降解参数。结果表明：不同紫花苜蓿品种DM，CP，NDF和ADF的降解率随着其在瘤胃内培养时间的延长，均呈升高趋势，但不同品种在同一培养时间段内的降解率存在显著差异；不同紫花苜蓿品种的有效降解率（ED）的差异较大，‘WL-319HQ DM’的ED最高，显著高于‘中苜一号’和‘首领’（P<0.01）；‘金皇后’CP的ED显著高于除‘赛迪’之外的其他品种；‘WL-168HQ’、‘中苜一号’NDF的ED显著高于除‘首领’之外的其他品种；‘三得利’、‘皇后’ADF的ED显著高于其他品种（P<0.05）。由此可见，不同紫花苜蓿品种在瘤胃内的降解特性不同。

关键词: 紫花苜蓿, 尼龙袋法, 瘤胃降解