ARS | Publication request: THE EFFECTS OF AGRADO ON THE PERFORMANCE AND ANTIOXIDANT STATUS OF FEEDLOT STEERS

Submitted to: Proceeding of Plains Nutrition Council Symposium
Publication Type: Abstract Only
Publication Acceptance Date: April 14, 2000
Publication Date: N/A

Technical Abstract: The effects of dietary Agrado on antioxidant status, ruminal VFA concentrations, daily gain, and volatile N losses were determined. Eighty steers (219 kg) were transported to the University of Arkansas, held in the facility for 42-d, and fed either a control or 150-ppm Agrado diet. Steers were then transported to the Texas Agricultural Experiment Station/USDA-ARS Sresearch feedlot in Bushland, TX. Steers were allotted to 8 pens and were fed either a control diet or 150-ppm Agrado in a 2 x 2 factorial arrangement. Blood was drawn on d 0, 28, and 87 post-transit and cattle weights were obtained at 28 day intervals. Rumenocentesis was performed on 10 steers per treatment on d 5 and 28 to determine ruminal fluid VFA concentrations. Samples of excreta were collected from the surface of each pen and volatile ammonia was determined using in vitro chambers. Compared to controls, steers fed Agrado in Arkansas had lower serum vitamin E concentrations (P<0.05) pre-shipment (1.93 vs. 2.23 micrograms/ml) but higher (P<0.04) vitamin E concentrations upon arrival at Bushland. Steers fed Agrado post-shipment had greater vitamin A concentrations (P<0.03) compared to control steers on d 28 and 87. All other antioxidant concentrations did not differ. Feed intakes and daily gains were greater (P<0.05) for steers fed Agrado post-shipment (8.6 vs 7.2 and 1.61 vs. 1.45 kg/d, respectively). The proportion of butyrate in ruminal fluid was greater (P<0.03) for steers fed Agrado than controls. Excreta from pens fed Agrado had greater (P<0.03) ammonia volatilization compared to control pens. These results indicate that feeding Agrado in a typical feedlot diet could increase daily gains and affect serum concentrations of certain antioxidants in feedlot steers during the beginning of the feeding period.