– L. Galyean, W. T. Nichols, M. N. Streeter, and J. P. Hutcheson, Applied Animal Science 2023. 39:69–78 https://doi.org/10.15232/aas.2022-02366
Additional days on feed increased marbling scores, but hurt yield grade.
Performance and carcass measurements from 7 experiments with beef steers, 6 experiments with beef heifers, and 2 experiments with Holstein steers, representing a total of 687 pen observations, were analyzed. Cattle were fed high-grain diets and managed under industry-standard conditions. All experiments included extended days on feed.
Slope values in the overall analyses for all 3 classes of cattle were generally significant, reflecting increased final shrunk body weight and hot carcass weight, greater carcass fatness, and shifts toward higher quality grade and yield grade with extended days on feed.
Example application of the extended days on feed slope estimates for a feedlot beef steers fed for an additional 42 d beyond a typical feeding period:
