Intensive beef production: 10. Replacement of cereals with chopped straw

Abstract

SUMMARY 1. Two growth trials and a digestibility trial were carried out with 48 Friesian steers given diets containing approximately 5, 20, 35 and 50% chopped barley straw and concentrates up to 100%. 2. Rates of live-weight gain between 130 and 400 kg declined from 1·18 to 0·65 kg/day and carcass gain declined from 0·62 to 0·30 kg/day as the straw content of the diet increased from 5 to 50%. 3. Alimentary tract ‘fill’ increased from 10·5% of live weight with 5% straw to 21% of live weight with 50% straw, and killing-out percentage dropped from 55·5% to 48·3%. 4. Both dry-matter digestibility and apparent nitrogen digestibility were lowest for the diet with 50% straw.