The relative digestibility of the constituents of the carbohydrate complex of grasses at successive stages of growth with reference to their partition into crude fiber and nitrogen-free extract according to the standard method for feeding stuff analysis

Abstract

The structural constituents, natural cellulose, hemicelluloses and lignin, in graminaceous food materials, faeces, and the crude fibre isolated from these have been determined. The results showed that: (1) crude fibre is almost wholly composed of natural cellulose but that the method for its isolation underestimates the natural cellulose content of the feed and of the faeces; (2) natural cellulose is the most digestible portion and lignin the least digestible portion of the cell-wall structure. From this finding it is inferred that a closer association exists between the lignin and the hemicelluloses than between the former and the natural cellulose of the cell-wall complex; (3) with regard to roughages the standard feeding stuffs analysis does not divide the carbohydrate complex into substances of relatively low and substances of relatively high digestibility.