Effects of rumen-protected Capsicum oleoresin on dry matter intake, average daily gain, and carcass characteristics of finishing beef steers

Our objective was to evaluate growth performance and carcass characteristics of finishing steers fed rumen-protected Capsicum oleoresin supplements differing in the extent of ruminal protection and when provided at 2 dose rates. A total of 450 steers were stratified by BW into 1 of 30 pens (15 steers per pen), and pens were randomly assigned to 1 of 5 treatments in a 2 × 2 + 1 factorial arrangement: no additive (CON); a low or high dose of rumen-protected Capsicum oleoresin (77 mg/d for RPLO and 250 mg/d for RPHI); or a low or high dose of Capsicum oleoresin that was rumen protected to a greater extent (100 mg/d for HPLO or 322 mg/d for HPHI). Both products were delivered in the vitamin and mineral supplement. All steers received the same basal diet of (DM basis) barley grain (86.2%), barley silage (6.0%), canola meal (6.2%), and a vitamin and mineral supplement (1.6%). Although BW at the start of the study did not differ (P > 0.19), there was an interaction between supplement and dose (P = 0.034) where increasing the dose from HPLO to HPHI numerically reduced BW, whereas increasing dose from RPLO to RPHI numerically increased BW. Inclusion of Capsicum, rumen protection, and dose did not affect DMI, ADG, or G:F whether reported on a live-weight or carcass-adjusted basis. Hot carcass weight, DP, and rib-eye area were not affected (P ≥ 0.11). The proportion of carcasses grading Canadian YG 3 were not affected by Capsicum but were reduced (P = 0.005) for the high versus low inclusion rates. Use of Capsicum did not affect QG, but feeding the high versus low doses decreased (P = 0.016) the proportion of steers grading AAA and increased (P = 0.009) the proportion grading AA. Marbling score was increased with the low versus high dose of Capsicum (P = 0.032). There were no differences for liver scores. Dietary supplementation of rumen-protected Capsicum did not affect DMI, growth, or carcass weight for finishing steers. However, increasing the dose of Capsicum may negatively affect carcass yield, QG, and marbling score.