To determine if fecal shedding of E. coli O157 and Salmonella is reduced by feeding orange pulp to experimentally infected sheep.
Orange juice production results in the waste products orange peel and orange pulp. These by-product feedstuffs have a high nutritive value for cattle and are often included in cattle rations as a least-cost ration ingredient. These by-products include essential oils which exhibit antibacterial properties against cattle-associated pathogenic foodborne bacteria, such as Salmonella and E. coli O157:H7. This study indicates feeding orange peel or dried orange pulp to sheep (as a model of cattle) reduced Salmonella and E. coli O157:H7 populations in the rumen, rectum and cecum at least 10-fold. Feeding of orange pulp at levels up to 10% of the ration were most effective in controlling populations of Salmonella and E. coli O157:H7 in the sheep. Orange pulp feeding also reduced survival of Salmonella and E. coli O157:H7 in cattle feces in test tube fermentations. Collectively our results indicate that feeding this commonly available feedstuff can reduce pathogen populations in food animals. This is an antipathogen strategy that can be implemented in various farms along the beef production continuum, and included in dairy rations prior to their entry to the beef supply. The availability of a green feedstuff that is economically feasible and results in an improvement in human food safety is an exciting development for the beef industry.