Utilizing a trace mineral (TM) injection approximately 90 d prior to harvest may improve growth performance and carcass characteristics when the β-agonist Optaflexx is not used. This may provide a unique opportunity for TM injection to be used in natural programs, to avoid the use of β-agonists, but still maintain high rates of growth. However, using a TM-injection only 28 d prior to harvest appears to have no additional benefit, and may decrease carcass quality.