3Burroughs W. Evaluation protein nutrition by metabolizable protein and urea fermentation potential[J]. J Dairy Sci, 1975,58 : 611 -619.
4Den Braver E J. Determnation of metabolizable energy in straw for ruminants by in vivo methods[J]. J agvic Res, 1976,4:53.
5Czerkawsiki J W, G Breckenridge. Desigen and development of long-term stimulation technique [J]. Brith J Nutri, 1977,38:371.
6Meng Q X. The requirement of ruminal degradable protein for non-structural carbohydrate fermenting microbes and its reaction with dilution rate in continuous culture [J]. Asian-Aus J Anim Sci,2000,13 (10) : 1399- 1406.
7Kirkpatrich B K,Kennelly J J. Prediction of digestibility in cattle using a modified nylon bag technique [Jl. Can J Anim Sci, 1984(64): 1104.
8Drskov E R. Protein nutrition in ruminants[M]. New York:Academic Press, 1992.
9Richardson C R. The limiting amido acid in growing cattle[J].J Anita sci,1978,46:740.
10Sterm M D. Effect of lignosulfonate on rumen microbial degradation of soybean meal protein in continuous culture[J]. J Anim Sci,1984,64(SuppL 1) :27.