期刊
AGRICULTURAL AND FOOD SCIENCE
卷 15, 期 3, 页码 219-234出版社
AGRICULTURAL RESEARCH CENTRE FINLAND
DOI: 10.2137/145960606779216254
关键词
calcium; magnesium; potassium; phosphorus; sodium; sulphur; digestibility
The effects of rapeseed and soybean expeller on digestion of sodium, potassium, calcium, magnesium, phosphorus and sulphur in dairy cows were investigated in a study conducted as an incomplete Latin square. The experimental diets consisted of five concentrates fed at a rate of 9 kg d(-1): a mixture of barley and oats (control), which was replaced either with rapeseed or soybean expeller both at two levels (130, 180 and 230 g crude protein per kg dry matter). A mixture of grass and red clover silage (1:1) was fed ad libitum. No mineral supplements except for NaCl and trace minerals were used. Ruminal digestion was estimated by omasal sampling technique and total digestion from total faecal collection. Intake of all minerals except sodium increased with the level of protein supplementation and it was generally higher when rapeseed compared with soybean expeller diets were offered. Reticulo-rumen was the major site of net absorption of magnesium, whereas calcium, phosphorus, sodium and potassium were absorbed postruminally. Net absorption of sulphur took place both in the rumen and postruminally. Omasal flow of sodium and phosphorus indicated substantial secretion of these minerals into the rumen via saliva. Compared with the published data based on duodenal sampling, the results indicated that omasum has an important role in the absorption of minerals, especially sodium and phosphorus. Omasal sampling technique is a useful tool in studying ruminal mineral metabolism.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据