Abstract In this study, 20 young steers received no beta-agonist (C) and 100 animals all received zilpaterol hydrochloride (Z), with 1 group receiving Z while the other 4 groups receiving Z and vitamin D3 at the following levels (IU/animal/day) and durations before slaughter: 7million for 3days (3D7M) or 6days (6D7M), 7million for 6days with 7days no supplementation (6D7M7N) and 1million for 9days (9D1M). Left carcass sides were electrically stimulated (ES) and right sides not (NES). Samples were analysed fresh or vacuum-aged for 14days post mortem. Parameters included drip loss and instrumental colour measurements. In general, zilpaterol showed increased drip loss, lighter meat, and reduced redness. Vitamin D3 supplementation could not consistently overcome these negative effects. All vitamin D3 treatments reduced drip loss of stimulated aged steaks.