Intake and Digestibility in Steers Fed Grass Hay Supplemented With Corn or Barley and Fish Meal or Soybean Meal

Twenty crossbred steers (493 ± 6 kg) were used to study the effects of two types of cereal (cracked corn or rolled barley) and two protein supplements (fish meal or soybean meal) on voluntary intake and apparent digestibility of grass hay based diets for beef steers. Diets contained 65% concentrate and 35% roughage as fed. Daily digestible energy intake, expressed as MJ kg−0.75 body weight, was 15% higher in steers fed barley (P < 0.01) and 10% higher when fish meal was fed instead of soybean meal (P < 0.04). Apparent digestion coefficients of DM and acid detergent fiber were similar for the four diets. Apparent protein digestibility was 30.5% higher in steers receiving barley (P < 0.01). Energy digestibility was slightly higher (6.5%, P < 0.14) for animals receiving barley compared with those receiving corn, probably because digestibility of barley starch was 7.3% higher (P < 0.01). Thus, digestible energy values of barley diets were 6.3% higher than those of corn diets. The results suggest that rolled barley was superior to cracked corn and fish meal superior to soybean meal when fed with grass hay to steers.