Competitive Exclusion/Colonization Resistence

Kenneth Genovese, USDA, College Station, TX

The increased concerns about antibiotic resistant bacteria being passed from food animals to humans has caused scientists, producers, and the public to investigate alternative methods for pathogen control and growth promotion in food animals that do not induce the emergence of antibiotic resistant bacteria. Tons of antimicrobials are fed to food animals each year both for growth promotion and as prophylactic measures against various diseases affecting food animals indicating the food animal industry’s reliance on these agents to be profitable. To meet the demand for the removal of many antimicrobial agents used in animal agriculture, producers will need alternative methods of pathogen control and growth promotion. Studies in our laboratory have focused on the use of animal derived normal gut bacterial microflora in the prevention of intestinal colonization of food animals by pathogens associated with both food born disease and disease affecting the animal as an alternative to the use of antimicrobial agents. These gut microflora, termed competitive exclusion (CE) cultures, when administered to neonatal animals, have been shown to be effective against Salmonella and Escherichia coli infections in both chickens and swine. We have shown decreased shedding, intestinal colonization, and reduced mortality and morbidity associated with Salmonella infections in chickens and both Salmonella and E. coli infections in swine. As pressure for the removal of growth promoting and prophylactic antibiotics in food animals continues to increase from various groups in the public and scientific sectors, the need for alternative ways of controlling disease and for promoting growth in food animals has become more urgent. We believe that the use of CE cultures may be an alternative to antimicrobial use in animal agriculture which could be used on its own or in combination with other alternatives for reducing pathogens in animals destined for human consumption.

Kenneth J. Genovese, Research Microbiologist, USDA/ARS, Southern Plains Agricultural Research Center, Food & Feed Safety Research Unit, 2881 F&B Road, College Station, TX 77845, USA, Tel: (979) 260-3756, Fax: (979) 260-9332, Em: Genovese@ffsru.tamu.edu