Bacteriophages a Possible Alternative to Antibiotics in Animal
By Jim Core
September 21, 2001
Agricultural Research Service scientists
have found encouraging results with an experimental way to reduce foodborne
pathogens and treat various poultry diseases. Early success in the
laboratory with bacteriophages could open the door to another way of preventing
and treating animal disease.
Escherichia coli bacteria cause respiratory disease in poultry,
leading to death or condemnation of the carcasses during processing.
Bacteriophages are viruses that infect bacteria and can kill them. A particular
phage can usually infect only one or a few related species of bacteria.
Scientists at the ARS Poultry
Production and Product Safety Research Unit, Fayetteville, Ark., isolated a
number of bacteriophages that would target a particular strain of E.
coli that causes disease in poultry, according to William E. Huff, a
poultry physiologist at the Fayetteville lab. They used E. coli serotype
02 to cause an air sac infection, called air saculitis, in broiler chickens.
When a bacteriophage was mixed with the E. coli strain prior to
challenging broiler chickens with the bacteria, the scientists were able to
completely protect the animals from respiratory infection.
Researchers chose air saculitis because it is very difficult to treat,
according to Huff. There may be other bacteriophage strains that are better
suited to attack the bacteria they used in their experiments, he added.
Bacteriophages were first discovered in 1915, but research on their
therapeutic use was largely abandoned outside of Eastern Europe when antibiotic
drugs became widely available in the 1940s.
The ARS researchers recently began their next step to investigate the
effectiveness of the phages to not only prevent but to treat an infection in
poultry. This research offers the possibility that bacteriophages could be
developed as an alternative to antibiotic use in poultry production, according
to Huff. He is also investigating the efficacy of bacteriophages against other
foodborne pathogens, such as Salmonella and Campylobacter. He has
isolated bacteriophages to Salmonella in cooperation with the
University of Arkansas.
ARS is the U.S. Department of
Agricultures chief scientific research agency.