The effect of short-term grain feeding on liveweight gain and beef quality

Two serial slaughter experiments were conducted to compare the liveweight g ain and carcass quality of 3-year-old Angus steers finished on concentrate- based rations with steers finished on high quality spring pasture in New Ze aland. Experiment 1 used a feedlot ration of 70% maize grain and 30% pastur e silage and Experiment 2 used barley instead of maize. In both experiments , steers were adjusted to the concentrate ration prior to being fed ad libi tum for 12 weeks. Finishing regime led to a significant difference in carcass weight in Exper iment 1 (363 and 407 kg for pasture and grain, respectively). There was no significant difference in final carcass weight in Experiment 2. There was n o significant effect of feeding regime on marbling in either experiment. Al though grain-finishing significantly affected pH in Experiment 1, there wer e no treatment effects on tenderness in either experiment, and resident New Zealand panellists were unable to detect sensory differences between beef from the two feeding regimes when comparisons were made at the same slaught er time. In both experiments, steers fed the concentrate diet had brighter and redder meat, but this may have been related to the reduced level of exe rcise of the feedlot group rather than diet per sc. Diet had no effect on c arcass fat colour in Experiment 1 but steers fed the feedlot ration in Expe riment 2 had significantly whiter fat colour. In these experiments the effects of short-term grain finishing on meat qual ity were minor. It was concluded that, provided a high growth rate and adeq uate level of finish could be achieved, beef produced from pasture finishin g was similar in tenderness and taste to beef finished for up to 100 days o n a feedlot.