This work aimed to evaluate post ruminal digestion of protein sources, by mobile nylon bags introduced in the duodenum of fistulated steers and collected from faeces. The feedstuffs were previously incubated in the rumen or separated the water soluble fraction before the intestinal digestion test. The soybean meal at 5% passage rate showed the highest ruminal protein degradability (73%) and highest intestinal digestibility (98%). Gluten meal was the least rumen degradable protein (16%) and showed a high digestible undegradable protein (95% if rumen incubated previously). Cottonseed meal and castorbean meal had similar patterns of digestion with total digestible protein of 95% and about 70% of rumen degradability. Rumen incubated palmist meal was less digestible (87% of total digestibility). Animal origin meals were less digestible either in the rumen or in the intestine, with total digestibility of 75% for meat and bone meal, 85% for feather and viscera meal and for fish meal I, 67 % for fish meal II and only 46% for blood meal.
bovine; intestine; digestibility; mobile bags; protein source
