The nutritive value of processed roughages for fattening cattle and sheep

Abstract

A roughage begins to be processed as soon as it is cut, receives further processing during preservation and possibly more after it has been preserved. At each stage, the processing has a potential or an actual effect on the nutritive value of the feed, but in this review we shall concern ourselves solely with processes applied after preservation has taken place. Roughages are processed mainly with the intention of increasing their energy value and their acceptability to the animal (although there may be other nutritional aims such as reducing the solubility of protein, or non-nutritional aims such as facilitating transportation or storage). Most of these processes are mechanical, but some—such as heat treatment—are better classified as physical and others —such as delignification with sodium hydroxide—are chemical.