Abstract: The experiment was conducted to evaluate the effect of urea and sodium hydroxide (NaOH) on the composition and disappearance of dry matter, neutral detergent fibre, acid detergent fibre, hemicellulose, cellulose and lignin of crushed rice straw, wheat straw and maize stover. The results show that NaOH and urea treatment have obvious effects on the components of the crop residues. 5 % NaOH (7 days at 23℃) and 5 % urea (28 days at 27℃) can improve the disappearance of cellulose, hemicellulose and lignin significantly in the rumen.

Key words: Crop residues, Urea treatment, Sodium hydroxide treatment