The utilization of ammonia-treated whole wheat grain by young steers

Abstract

ABSTRACT Wheat grain was given whole (W), cracked (C) or ammonia-treated (N) as the sole diet to six steers. In Expt 1, W, C and N were given at the rate of 2·1 kg per head per day. In Expt 2, W and N were given at the rate of 7·35 kg per head twice weekly; feeding of C had to be abandoned due to frequent bloat. Dry-matter digestibility was 0·79, 0·86 and 0·88 on W, C and N in Expt 1 and 0·75 and 0·83 on W and N in Expt 2. The digestibility of neutral detergent fibre was 0·37, 0·24 and 0·57 with diets W, C and N respectively in Expt 1 and 0·27 and 0·47 with diets W and N in Expt 2. The quantity of whole grain voided in faeces (g/kg grain fed) was 122, 3 and 31 with W, C and N in Expt 1 and 136 and 51 with W and N in Expt 2. Voided grains had a lower ratio of cr-glucose: neutral detergent fibre than grains fed, which indicated partial digestion of starch. Rates of nitrogen retention (g/day) were 6·6, 9·4 and 9·8 with W, C and N in Expt 1 and 7·2 and 12·2 with W and N in Expt 2. It was concluded that ammonia-treated whole wheat grain is utilized as efficiently as cracked wheat grain when given as a sole diet to cattle and results in fewer digestive disturbances than cracked wheat grain.