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Growth adjustment to diet improves profitability within the feedlot
Feed efficiency improvement can increase beef production profitability. Our objective was to compare feeding system (SYS) affect on efficiency, carcass composition and feedlot profitability. We hypothesized sorting cattle by initial ADG and feeding subsequent diets formulated to match growth potential would increase gain efficiency and profitability compared with traditional feeding programs. Heifers (n = 287; 224.70 ± 1.4kg) purchased through livestock markets were fed a diet formulated to meet effective energy (EE) and AA requirements for 2.1 kg ADG over 42 d following a 14 d receiving period. From the 42-d ADG, heifers were blocked as high (1.98 to 2.71 ± 0.18 kg/d), mid (1.67 to 1.97± 0.08 kg/d) and low (0.54 to 1.70 ± 0.22 kg/d) ADG and were stratified across SYS. Diets were formulated without forage inclusion for matched (M) and nontraditional (NTRAD) SYS. High (HM), mid (MM) and low (LM) blocks within the M SYS were formulated to meet EE and AA requirements. High, mid and low blocks were not separated in either traditional (TRAD) or NTRAD SYS. The TRAD SYS was fed a diet formulated to meet NRC requirements, while the NTRAD SYS was fed the MM diet. Diets were fed from day 43 until slaughter, however, HM and MM SYS were transitioned as needed to the LM diet to adjust for decreasing finishing period nutrient requirements. Heifers were slaughtered when gain cost exceeded value of gain, visually-assessed back fat ≥ 0.76 cm, and estimated HCW ≥ 243.2 kg. Final BW and ADG were not different (P > 0.10) among SYS. Additionally, HCW, LM area, back fat thickness, yield grade and quality grade were not different (P > 0.10) among SYS. Nontraditional and M SYS had less DMI (7.32 and 7.40 vs. 8.36 kg ± 0.30; P ≤ 0.001) and feed conversion ratios (5.97 and 5.86 vs. 6.59 ± 0.30; P ≤ 0.001) than TRAD. Diet cost for TRAD was less ($0.327/kg; P ≤ 0.001) than both NTRAD ($0.347/kg) and M ($0.346/kg) SYS. No SYS resulted in profit; however, loss per heifer was less (P = 0.02) for M (-$6.20) compared with TRAD (-$51.88), where loss per heifer for NTRAD was not different (P ≥ 0.10) from either M or TRAD. In conclusion, forage removal combined with balancing for EE and AA growth performance requirements can increase feedlot efficiency and profitability.
Keywords: beef, feed efficiency