In situ ruminal dry matter and crude protein degradability of plant- and animal-derived protein sources in Southern Turkey

Twelve plant- and animal-derived protein sources (fish meal, meat meal, meat and blood meal, blood meal, poultry by-products meal, cottonseed meal, sunflower meal, corn germ meal, rapeseed meal and hazelnut meal) were evaluated in terms of dry matter (DM) and crude protein (CP) degradation in situ in the rumen of sheep. There were significant differences between protein sources in terms of DM and CP disappearance and degradability. Effective degradabilities of DM of soybean meal at three outflow rates were significantly higher than those of the other protein sources except corn germ meal, rapeseed meal and hazelnut meal, whereas effective degradabilities of CP of soybean meal at three outflow rates were significantly higher than those of all the other protein sources. Animal-derived protein sources such as meat and bone meal, blood meal, poultry by-products and fish meal had significantly lower effective DM and CP degradability values than those of soybean, corn germ meal, rapeseed meal and hazelnut meal. Therefore, animal-derived protein sources with a low degradability can be used to increase the bypass protein. The CP degradation parameters obtained in this experiment using sheep would be very useful in improving the accuracy of formulation of sheep diets. © 2004 Elsevier B.V. All rights reserved.