Growth, feed efficiency and variation of individually fed Angus, polled Hereford and Holstein steers

Individual growth and feed intake of 36 Angus, 27 Polled Hereford and 30 Holstein steers were determined from 365 to 560 kg live weight. One-half of the cattle in each breed were fed a diet based on high-moisture ear corn and the other one-half were fed a diet based on corn silage. Within each breed X diet group, half of the cattle were implanted with zeranol. Cattle fed the high-moisture ear corn diet were 8% more (P less than .01) efficient than cattle fed the corn silage diet. Cattle implanted with zeranol consumed 9% more (P less than .005) dry matter and gained 15% (P less than .005) faster, resulting in 5% (P less than .05) less dry matter per unit gain than unimplanted cattle. Holstein steers gained 11% faster (P less than .005) and consumed 8% less (P less than .025) dry matter per unit gain than the average of Angus and Polled Hereford steers. Within subclass coefficients of variation were 9.9, 14.3 and 13.7 for daily dry matter intake, average daily gain and dry matter per unit gain, respectively; within subclass correlations were .50 (P less than .01), .17 and -.75 (P less than .01) between daily dry matter intake and average daily gain, daily dry matter intake and dry matter per unit gain and average daily gain and dry matter per unit gain. When combined with previous data that show Holsteins attain the Choice grade with less trimmable fat and equal weight of trimmed primal cuts compared with traditional beef breeds of the same live weight, these results suggest that Holstein steers are under-valued feedlot beef cattle.