Cholecalciferol supplementation of heifer diets increases beef vitamin D concentration and improves beef tenderness

This study investigated the effects of cholecalciferol (vitamin D₃) supplementation on beef vitamin D activity, beef tenderness and sensory attributes. Thirty heifers were randomly allocated to one of three finishing dietary treatments [(T1) basal diet + 0 IU vitamin D₃; (T2) basal diet + 2000 IU vitamin D₃; and (T3) basal diet + 4000 IU vitamin D₃] for a 30 day period pre-slaughter. Vitamin D₃ supplementation linearly increased serum 25-hydroxyvitamin D₃ (25-OH-D₃) concentrations (R² = 0.48), Longissimus thoracis (LT) total vitamin D activity (R² = 0.78) as well as individually vitamin D₃ (R² = 0.84) and 25-OH-D₃ (R² = 0.75). The highest vitamin D₃ inclusion diet (T3) had a 42% increase (P < 0.001) in LT vitamin D activity compared to the intermediate diet (T2) and a 145% increase over the lowest level diet (T1). Vitamin D₃ supplementation decreased LT shear (P < 0.05) force values after 14 days chilling. Sensory parameters were not affected (P > 0.05). In conclusion, through short-term vitamin D₃ supplementation of cattle diets, beef vitamin D activity can successfully be enhanced.