Effects of a Single α-Tocopherol Injection on Pre-Weaning Average Daily Gain and Serum Metabolites of Beef Steer and Heifer Calves

The objective of this trial was to evaluate the impact of an α-tocopherol injection on pre-weaning calf performance including markers of growth and behavior. Sixty-one days prior to weaning, both nursing Angus and Hereford steer calves (SC; n = 16) and Angus and Hereford heifer calves (HC; n = 28) were randomly assigned to one of two treatments: (1) no injectable α-tocopherol (CON; n = 23) or (2) 1500 IU of injectable α-tocopherol administered subcutaneously (VitE; n = 21). Average daily gain (ADG), exit velocity (EV), serum urea nitrogen, serum cortisol, and serum α-tocopherol concentrations were evaluated on d 0, 28, and 61 of the trial. Steer calves increased (p = 0.01) ADG compared to HC, with SC gaining about 13% more than HC. There was no impact (p ≥ 0.20) of injectable vitamin E on calf ADG. As the trial progressed, EV slowed (p = 0.0005) in both HC and SC regardless of treatment. Serum α-tocopherol concentrations were influenced (p = 0.04) by an interaction of treatment, sex, and time, with CON-SC being the only group that did not have serum α-tocopherol concentrations decrease throughout the trial. Overall, this trial found that a pre-weaning vitamin E injectable did not improve pre-weaning calf performance, but calf sex did.