Effect of feed intake level and feeding regime on feedlot performance and carcass characteristics of yearling steers
Allen H. Trenkle
The effects of feed intake level and feeding time on feedlot performance and carcass characteristics were evaluated in two studies. The feed intake levels were ad libitum, 95% of ad libitum and 90% of ad libitum. There were three feeding times: once per day at 0800, feeding once per day at 1600, and feeding twice per day at 0800 and 1600. A reduction in daily feed intake did not significantly reduce feedlot performance and at the same time improved quality grade. Based on the performance and carcass data for the limit fed cattle, a series of example budgets was created to evaluate the economic advantage of limiting the dry matter intake of feedlot steers. Cattle limited to 95% of ad libitum intake had the highest profit potential. Frame score five yearling beef steers fed a whole corn grain and chopped alfalfa hay diet, and started on feed during the summer months, were used to develop an equation which predicted daily dry matter intake (R2=.71). Multipliers to adjust the model for season, shelter type, diet, frame size, and Holstein steers were estimated as well. The equation was: Steer DMI (kg/d) = (-171.130 +.0245 PW -.0309 TDOF + 3.283 NDF + 58.961 NEm) x M. Where PW was the current average body weight in kg, TDOF was total days on feed, NDF was percent neutral detergent fiber in the diet, NEm was net energy for maintenance in the diet (Mcal/kg), and M was the adjustment multiplier. The adjustment multiplier for frame score 6 steers was -.7356. The multiplier for Holstein steers was -.4211. The multiplier to adjust for winter feeding conditions was -.5854 for steers weighing less than 364 kg and -.6853 for steers weighing more than 364 kg. The multiplier for cattle raised with access to a windbreak was 1.0657 for beef steers and 1.0733 for Holstein steers. The multiplier for cattle fed a corn silage diet was -.4372.