常用精料干物质和脂肪在瘤胃中降解规律的研究

本试验用尼龙袋技术测定了肉牛常用精料玉米、芝麻饼、菜籽粕、豆粕、棉籽粕、油葵粕、棉籽饼、大豆和鸡杂的干物质和脂肪在瘤胃中的降解率。结果表明，４８小时的大豆干物质降解率最高，达９６．８％，其次是大豆粕、玉米和芝麻饼，分别为８９．３％，８９．０％、８８．４％，再次是菜籽粕、棉籽粕和棉籽饼，分别为７９．２％、７８．４％和７７．６％。鸡杂的干物质降解率为６６．５％，在所测定的样品中最低。４８小时的棉籽粕、菜籽粕、大豆和大豆粕的脂肪降解率最高，分别为９８．９％、９８．７％、９８．５％、９６．９％。其次是棉籽饼、芝麻饼、鸡杂、油葵饼和玉米，分别为９３．７％、８９．７％、８８．６％、８８．３％、８３．６％。尽管鸡杂是动物性饲料，但４８小时的脂肪降解率与其它植物性饲料的脂肪降解率差别并不大。

Study on the Degradation of Dry Matter and Fat of Concentrates in the Rumen of Steers Measured with Nylon Bag Technique

The degradabilities of matter and fat of commonly used concentrates such as corn,sesame meal,rapseed meal,soybean meal,cottonseed meal,sunflower meal,cottonseed cake,soybean and chicken giblets were determined with nylon bag technique.Results show that at 48 bour of incubation,the dry matter degradability of soybean is 96.8%,which is the highest in all feeds.The dry matter degradability of soybean meal,corn,sesame meal,rapeseed meal,cottonseed meal and cottonseed cake are 89.3% ,89.0% and 88.4%,79.2%,78.4% and 77.6%,respectively.The dry matter degradability of chicken giblets is 66.5% ,which is the lowest in all feeds.The fat degradability of cotton seed meal,rapseed meal,soybean,soybean meal,cottonseed cake,sesame meal,chicken giblets,sunflower meal and corn are 98.9%,98.7%,98.5%,96.9%,93.7%,89.7%, 88.6 %, 88.3 % and 83.6%,respectively.