Supplemental β-carotene I: Effect on plasma vitamin A, growth, performance, and carcass characteristics of feedlot cattle

To evaluate the effects of β-carotene (βC) on performance and carcass characteristics, 112 crossbred calves were allotted to 4 treatments consisting of retinyl palmitate (RP) supplemented at 2200 IU/kg, and synthetic β-carotene supplemented at 1 (SβC1X), 5 (SβC5X), or 10 (SβC10X) times RP. Compared to RP, SβC1X did not impact performance (P ≥ 0.25) or plasma concentrations of retinoids or carotenoids (P ≥ 0.26). Increasing dietary βC increased (P ≤ 0.04) plasma concentrations of RP and all of the isomers of βC, but did not affect weight, gain, or gain:feed (P ≥ 0.24). Marbling and fat thickness did not differ between RP and SβC1X or because of amount of βC (P ≥ 0.35). Lightness (L*) of LM decreased with increasing concentration of SβC (linear; P = 0.01). Yellowness (b*) increased (P = 0.04) and redness (a*) tended to increase (P = 0.09) in subcutaneous fat as SβC amount increased (quadratic).