In the study, the researchers isolated a number of naturally occurring bacterial viruses (called bacteriophage) that can infect and kill campylobacter bacteria from the feces of chickens. They then used these bacteriophage to treat chickens that were infected with campylobacter.
"Campylobacter bacteriophage are naturally present in chickens and have no recorded detrimental effect on the health of chickens or human beings," says Catherine Loc-Carrillo, a researcher on the study. "In nature a balance exists between predator and prey which allows both [the bacterium and the bacteriophage] to flourish. Here the use of bacteriophage to reduce campylobacters within the chicken gut merely involves shifting nature's balance in our favor for a short period of time. This time point should be just prior to when the birds are sent for slaughter."
This brief shifting of nature's balance, in this case, resulted in a 100- to 100,000 fold reduction in the number of bacteria in the chickens' intestines over a 3-day period. The amount of the reduction was dependant on both the particular bacteriophage used and the dose administered.
"The selection of the bacteriophage is critical for this application since not all bacteriophage are effective," says Loc-Carillo.
This study was funded by the United Kingdom Government's Food Quality and Safety Link initiative with a consortium of poultry producers and food companies.
This release is a summary of a presentation from the 104th General Meeting of the American Society for Microbiology, May 23-27, 2004, in New Orleans, Louisiana. Additional information on these and other presentations at the 104th ASM General Meeting can be found online at http://www.