Submitted to: Texas A&M Research and Extension Center Progress Report
Publication Type: Abstract Only
Publication Acceptance Date: 8/1/2000
Publication Date: N/A
Citation: N/A Interpretive Summary:
Technical Abstract: The synthetic antioxidant Agrado (ethoxyquin) was fed to beef steers before and after transport from Arkansas to Texas to determine the effects on antioxidant status, animal performance, ruminal VFA concentrations, and emissions of nitrogen from the feedyard surface. Eighty feeder steers averaging 481 lb were fed diets containing either 0 to 150 mg of Agrado/kg for 42 days in Arkansas. Blood samples were obtained on day 42 and calves were transported by truck to Bushland, TX. On arrival calves were weighed, blood samples were obtained, and calves were sorted to eight pens. Calves were fed receiving diets containing either 0 to 150 mg of Agrado/kg in a 2 x 2 factorial arrangement. Calves were weighed at 28 day intervals and blood samples were obtained on days 28 and 87. Ruminal fluid samples were obtained on days 5 and 28. Samples of feces were collected from the pen surfaces and in vitro ammonia losses were determined. Steers fed Agrado in nthe feedlot had greater (P < 0.05) daily gains than control steers. Steer fed Agrado had higher plasma vitamin A concentrations than control steers on days 28 and 87 in the feedlot but plasma concentrations of vitamin C, vitamin E, and uric acid and whole blood selenium were not affected by Agrado. On day 5 in the feedlot, steers fed Agrado had higher ruminal concentrations of butyrate than control steers. Ruminal VFA concentrations were similar for both diets on days 28. The excreta harvested from pens containing steers fed Agrado had greater (P < .05) ammonia volatilization than control pens. These results suggest that the feeding of Agrado could potentially improve performance of steers in the feedlot and may affect certain antioxidant concentrations early in the feeding period.