Effect of stage of maturity of whole-crop barley on intake and liveweight gain by dairy steers differing in initial live weight

The effect of maturity at harvest of whole-crop barley for ensiling on intake and liveweight gain of dairy steers differing in initial live weight (LW) was evaluated in an experiment over two years. Light (104-120 kg) and heavy (402-419 kg) dairy steers were fed diets containing predominantly whole-crop barley silage harvested at the milk stage [dry matter (DM) content of 284 g kg(-1) and neutral-detergent fibre (NDF) concentration of 526 g kg(-1) DM] or the dough stage of maturity (DM content of 328 g kg(-1) and NDF concentration of 445 g kg(-1) DM) and supplemented with up to 1 kg of concentrate. Dry matter intake (g kg(-1) LW) was higher for whole-crop barley harvested at the dough stage than at the milk stage of maturity and the difference was greater in heavy than in light steers (P < 0 center dot 001). Liveweight gain was higher and feed conversion ratio was lower for dough-stage compared with milk-stage silage (P < 0 center dot 05) but there was no interaction with size of steer. Whole-crop barley harvested at the dough stage of maturity promoted higher liveweight gains in dairy steers compared with whole-crop barley harvested at the milk stage due to a higher DM intake.