Submitted to: Safepork
Publication Type: Proceedings
Publication Acceptance Date: May 30, 2005
Publication Date: September 6, 2005
Citation: Edrington, T.S., Genovese, K.J., Callaway, T.R., Schultz, C.L., Anderson, R.C., Nisbet, D.J. 2005. Influence of ractopamine supplementation on Salmonella in feeder pigs. Proceedings of SafePork 2005. p. 157-160. Interpretive Summary: Salmonella is a bacteria that can live in pigs, which can make pigs sick, and also people if they eat pork contaminated with Salmonella. Ractopamine is a chemical compound fed to growing pigs to improve performance and carcass quality and is similar to a hormone produced by the pig. These hormones have been shown to influence the growth of some harmful bacteria. We conducted this study to determine if feeding ractopamine to pigs would influence populations of Salmonella. Results indicate ractopamine may have the added benefit of reducing Salmonella populations in growing pigs.
Technical Abstract: The objective of the current study was to determine the effect of ractopamine supplementation on gut populations and fecal shedding of Salmonella in growing pigs. Sixteen crossbred pigs (avg. BW = 33 kg) were fed a grower ration with and without ractopamine (18 g/ton feed) for 38 days. Four days prior to termination of the study, all pigs were experimentally infected with Salmonella Typhimurium. Fecal samples were collected daily for quantification of the challenge strain and four days following inoculation, all pigs were euthanized and necropsied. Fecal shedding of Salmonella was decreased (P < 0.05) in pigs fed ractopamine. The number of Salmonella-positive tissue samples from the liver was decreased (P = 0.05) and the number of positive ileo-cecal lymph nodes tended (P = 0.13) to decrease in the ractopamine treatment. Results of this preliminary study indicate ractopamine may have the added benefit of reducing Salmonella populations in growing pigs.