34 Effects of rumen-protected Capsicum oleoresin on growth performance and immune response in growing beef cattle

Abstract

Abstract Objectives were to determine effects of rumen-protected Capsicum (RPC) on growth performance and immune response in growing beef cattle. Cattle were stratified by sex (steers = 24; heifers = 12) and body weight (BW; heavy or light) and randomly assigned to treatments: Control (no additive), or RPC (15 mg/kg of dry matter intake (DMI)). Cattle were transitioned over 21 days to a final diet of 80% grain mix and 20% corn silage. Cattle were weighed on test (d0 and 1), at end of adaptation (d21), at midpoint (d48 and 49), and off test (d98 and 99). Blood samples were collected on days 0, 21, and 98 for analysis of parameters related to immune function and energy status. Health treatments were recorded. Performance and blood variables (as repeated measures) were analyzed using the MIXED procedure of SAS. Pen was the experimental unit. Health data were analyzed using the GLIMMIX procedure; animal was the experimental unit. There was no interaction (P > 0.10) of treatment and sampling day, nor main effect of treatment (P > 0.10), for any blood parameters measured. There were no treatment effects (P > 0.10) on DMI or feed efficiency. From d0 to 21, average daily gain (ADG) tended to be greater (P = 0.13) for animals fed RPC and was 22.9% greater (P = 0.10) for animals fed RPC from d22 to 49. While only 14% of the heavy animals were treated two or more times, 66% of light animals were treated two or more times (P < 0.01), of which 77% were fed Control. Supplementing RPC improved early feedlot ADG. Although there were no changes in blood parameters, ADG improvement may be related to health status.