INTERVENTIONS TO REDUCE FOODBORNE PATHOGENS IN SWINE AND CATTLE
Location: Food and Feed Safety Research
Title: Lack of effect of feeding citrus by-products in reducing Salmonella in experimentally infected weanling pigs
Submitted to: Journal of Food Protection
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: November 2, 2011
Publication Date: March 1, 2012
Citation: Farrow, R.L., Edrington, T.S., Krueger, N.A., Genovese, K.J., Callaway, T.R., Anderson, R.C., Nisbet, D.J. 2012. Lack of effect of feeding citrus by-products in reducing Salmonella in experimentally infected weanling pigs. Journal of Food Protection. 75:573-575.
Interpretive Summary: Pigs are naturally infected with Salmonella, a bacterium that causes food sickness in humans. By-products of the citrus industry are reported to have anti-bacterial properties and are readily available during certain times of the year in citrus-producing regions of the United States. We investigated the ability of two citrus by-products (citrus molasses and D’limonene) to kill Salmonella in experimentally-infected weanling pigs. Results showed that these products were not effective in reducing the prevalence of Salmonella in the feces or in reducing the populations within various segments of the digestive tract suggesting they are unsuitable as a tool to reduce Salmonella in young swine.
The objective of the current research was to determine if feeding citrus by-products D’Limonene (DL) and citrus molasses (MOL) would reduce the concentration and prevalence of Salmonella in weanling pigs experimentally infected with Salmonella Typhimurium. Twenty crossbred weanling pigs (avg. BW = 19.9 kg) were randomly assigned to one of four treatments: Control, low DL (1.5 mL / kg BW / d), high DL (3.0 mL / kg BW / d), and MOL (0.05 kg / BW /d). Treatments were administered via mixing with the feed twice daily with one half dose at each feeding. Fecal samples were collected twice daily and cultured for quantitative and qualitative determination of Salmonella using standard culture techniques. Upon study termination, pigs were euthanized and tissues from the rumen, ileum, cecum, spiral colon and rectum, as well as their respective luminal contents were collected. In addition, the popliteal and ileocecal lymph nodes, liver, spleen, and tonsils were collected for qualitative Salmonella culture. No significant treatment differences (P > 0.05) were found for fecal Salmonella prevalence or concentration between treatment groups throughout the 7-day collection period. Furthermore, no treatment (P > 0.05) differences were observed for any of the tissue or content samples collected. Salmonella was not cultured from the muscle bound, popliteal lymph node, but was cultured from the mesenteric ileo-cecal lymph nodes. Salmonella continues to represent significant animal and human health concerns and further research to find cost effective control measures is warranted.