INTERVENTIONS TO REDUCE EPIZOOTIC PATHOGENIC BACTERIA IN SWINE AND CATTLE
Location: Food and Feed Safety Research
Title: Evaluation of gallium maltolate on fecal Salmonella shedding in cattle
Submitted to: Journal of Food Protection
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: January 7, 2011
Publication Date: May 1, 2011
Citation: Nerren, J.R., Edrington, T.S., Lawrence, B.R., Farrow, R.L., Genovese, K.J., Callaway, T.R., Anderson, R.C., Krueger, N.A., Nisbet, D.J. 2011. Evaluation of gallium maltolate on fecal shedding of Salmonella in cattle. Journal of Food Protection. 74:524-530.
Interpretive Summary: Cattle are naturally infected with Salmonella, a bacterium that causes food sickness in humans. Gallium maltolate is a compound that was found to kill Salmonella in laboratory experiments. We investigated the ability of gallium maltolate to kill Salmonella in experimentally infected cattle. Results showed that dosing gallium was not effective in reducing the prevalence of Salmonella in the feces or in reducing the populations within various segments of the digestive tract. These findings do not support the use of gallium maltolate as a tool to reduce Salmonella in live cattle prior to slaughter.
Salmonella is a major cause of foodborne illness in humans and causes over a third of all cases of gastroenteritis in the United States. Human foodborne outbreaks due to Salmonella have been traced to milk, beef, pork, and poultry. Fecal contamination of the carcass and hide is thought to be a major source of tainted meat products derived from cattle. Thus, strategies aimed at reducing fecal shedding of Salmonella and other foodborne pathogens may serve as an effective means for limiting transmission of pathogens from food animals to humans. The objective of this study was to determine if oral administration of gallium maltolate (GaM) would reduce fecal shedding of Salmonella in cattle. Gallium is a semi-metal that exhibits antimicrobial properties against some pathogenic bacteria, including Salmonella, by exploiting their requirement for iron to survive and replicate. We administered two doses of GaM to Holstein steers following experimental infection with Salmonella and monitored quantitative and qualitative fecal shedding in 12 h intervals. Sixty h after initiating treatment, cattle were euthanized, and luminal contents and tissue were aseptically harvested from the rumen, jejunum, spiral colon, cecum, and rectum. The luminal contents were processed for quantitative and qualitative analysis of the challenge strains of Salmonella, and tissue samples were enriched and plated for qualitative analysis. We found no significant differences between control animals and treated animals in quantitative levels of Salmonella in the feces or in the luminal contents. Likewise, we observed no pattern between control and treated animals in the frequency of positive or negative values in enriched feces, luminal contents, or tissue samples. Data from this study suggests that GaM was not effective at reducing fecal shedding of Salmonella.