Nutritive value of long or cut-rice straw when fed alone, or with added available nitrogen and energy

Abstract

Digestion and N balance were investigated in Egypt in 1988-89 using mature rams fed at maintenance level. Treatments tested were: (1) long rice straw; (2) cut rice straw; (3) long and cut rice straw with 1.5% urea (LRSU; CRSU); (4) rice straw with concentrate mixture and (5) rice straw with urea plus sugar-cane molasses. Maize replaced molasses in another experiment. Cutting rice straw improved digestibility of organic matter, crude protein and crude fibre. Urea addition improved the N balance and digestibility; better results were recorded for CRSU than LRSU. Urea plus molasses produced better results than the concentrate mixture. Maize replacing molasses improved digestibility and N balance. Rice straw fed alone produced a negative N balance whereas all other treatments resulted in positive balances. Cutting rice straw to about 5 cm is recommended for better utilization of its nutrients. The addition of urea plus either maize or molasses, preferably maize, is essential to provide N and energy lacking in rice straw. From authors' summary. Record Number : 19916776050