Growth Performance and Carcass Quality of Crossbred Holstein × Beef Heifers and Steers Fed High-Solid Milk in the Preweaning Period

This study aimed to determine whether greater weight gains in crossbred calves fed whole milk adjusted to 14% total solids during the preweaning phase persist into the postweaning and finishing phases and influence carcass grading. Eighty Holstein × beef calves (male and female) were randomly assigned to receive either pasteurized whole milk with 11% total solids (11%TS) or pasteurized whole milk supplemented with milk replacer to achieve 14% total solids (14%TS). Calf nutrition was modified only during the preweaning phase (<60 d). Calves fed the 14%TS diet received more nutrients than those fed the 11%TS diet, resulting in greater ADG (971 ± 16 vs. 851 ± 29 g; p < 0.01) and weaning weight (98.0 ± 1.29 vs. 93.2 ± 1.85 kg; p < 0.05). After weaning, and over a 49-week period, the gap in cumulative ADG in favor of the 14%TS group (+120 g) gradually decreased over time (only −5.6 g per month), yet consistently remained higher than that of the 11%TS group, resulting in a greater (p < 0.05) final BW (+17.5 kg) for calves in the 14%TS group than the control group (520.4 ± 3.6 vs. 502.9 ± 7.4 kg). In addition, a greater (p < 0.05) proportion of animals was assigned to higher-quality lots (sale lot assignment; 30/40; 75% in lot type 1 for 14%TS vs. 20/40; 50% for 11%TS) and a greater numerical proportion of carcasses was classified as Choice (27/40; 67.5% for 14%TS vs. 20/40: 50% for 11%TS), as determined by USDA-approved automatic grading. Ultimately, these advantages translated into greater estimated revenue per animal (USD 117 per calf) for the 14%TS group than the 11%TS group under USDA beef-grading scenario. In conclusion, the results of this study demonstrate that providing enhanced nutrition to beef-on-dairy calves improves growth performance during the preweaning phase, compared with the control group. This improvement persists over time, reflecting in favorable slaughter outcomes and numerical responses in carcass grading, thereby increasing revenue per animal and reinforcing the strategic value of beef-on-dairy systems. In addition, the financial advantages of implementing a payment method based on USDA beef grading classification are highlighted.