Date of this Version
The Professional Animal Scientist 22 (2006):225–235
One hundred sixty English-cross steers (244 kg, SD=23 kg) were used in each yr of a 2-yr study to determine effects of sorting on performance, carcass characteristics, variability, and profitability in a long yearling system utilizing ranch-source calves. Steers were back grounded during winter then grazed smooth brome-grass pastures followed by warm season native range prior to entering the feedlot in the fall. Steers were stratified by BW and allotted to 1 of 4 treatments: 1) 40 head sorted by pre-grazing BW where heavy steers entered the feedlot in July (PST), 2) 40 head sorted by BW entering the feedlot (FDL), 3) 60 head sorted by BW and fat thickness at the end of the feeding period (IND), and 4) 20 head that were not sorted (UNS). No differences were observed for performance during back-grounding or grazing phases (P > 0.30). Cattle receiving PST sorting weighed less entering the feedlot and consumed less feed with less feedlot ADG compared to other treatments (P < 0.05). No differences in feed efficiencies were detected (P = 0.84). Cattle receiving PST sorting had greater marbling scores (P < 0.05) and less variation in BW upon feedlot entry which resulted in less variation in carcass weight compared with UNS (P < 0.05). Cattle sorted by BW entering the feedlot tended (P = 0.08) to have less variation in carcass weight compared with UNS. There were no differences in carcass weight or profitability when calculated on either a live or value basis. No sorting strategy increased carcass weight, reduced discounts for overweight or corpulent carcasses, or improved profitability over UNS.