Submitted to: International Debate Conference for the Feed and Food Chain
Publication Type: Proceedings
Publication Acceptance Date: 9/29/2004
Publication Date: 1/1/2005
Citation: Huff, W.E., Huff, G.R., Rath, N.C., Balog, J., Donoghue, A.M. 2005. Bacteriophage: A safe and natural alternative to antimicrobial growth promoters. In: Proceedings of the International Debate Conference for the Feed and Food Chain Antimicrobial Growth Promoters: Worldwide Ban on the Horizon, January 31 - February 1, 2005, Noordwijk Ann Zee, The Netherlands. p. 60. Interpretive Summary:
Technical Abstract: Bacteriophage are viruses that infect and kill bacteria. Bacteriophage do not infect either animal or plant cells making them a potentially safe alternative to antibiotics to both prevent and treat bacterial diseases in animals and humans. Bacteriophage lytic to a sero-type 02 strain of Escherichia coli were isolated from municipal waste water treatment plants and poultry processing plants. This E. coli isolate is pathogenic to poultry, causing a severe respiratory and systemic infection. Two bacteriophage isolates were selected to use in studies designed to determine the efficacy of these bacteriophage to prevent and treat severe colibacillosis in poultry. Colibacillosis is induced by injecting 6 X 10**4 cfu of E. coli into the thoracic airsac when the birds are 1 week of age. Initial studies demonstrated that mortality was significantly reduced from 85% to 35% when the challenge culture was mixed with equal titers of bacteriophage, and the birds were completely protected when the challenge culture was mixed with 10**8 pfu of bacteriophage. In subsequent studies, we have shown that an aerosol spray of bacteriophage given to the birds prior to this E. coli challenge could significantly reduce mortality even when given 3 days prior to the E. coli challenge. Our research on treating colibacillosis in poultry has demonstrated that an intramuscular injection of bacteriophage given 24 or 48 h after the birds were challenged rescued the birds from this severe E. coli infection. In studies where bacteriophage and antibiotic therapy are combined we have demonstrated a significant synergistic interaction improving the therapeutic efficacy of both bacteriophage and the antibiotic. This research suggests that the levels of antibiotics used can be decreased if combined with bacteriophage therapy, which should increase the effective life of antibiotics. Our research has demonstrated that bacteriophage can be used to both prevent and treat colibacillosis in poultry and may provide an effective alternative to antibiotic use in animal production. The real challenge is how to make bacteriophage a practical alternative to antibiotics given the complexity of modern animal production systems.