Be careful what you feed those backyard chickens because foodborne bacteria can cause disease in some breeds of chickens after all, says new research, "Campylobacter jejuni Is Not Merely a Commensal in Commercial Broiler Chickens and Affects Bird Welfare," published online July 1, 2013 in the journal mBio®, the online open-access journal of the American Society for Microbiology. Contrary to popular belief, the foodborne pathogen Campylobacter jejuni is not a harmless commensal in chickens but can cause disease in some breeds of poultry according to new research. Campylobacter jejuni is the most common cause of food-borne bacterial diarrheal disease in the developed world. And chicken is the most common source of infection. Even one drop of juice from raw chicken meat can have enough Campylobacter in it to infect a person. And other research revealed that chickens from some farmers' markets have even more bacteria than from other types of food markets, according to the article, "Local Farmers Market Chickens May Have More Harmful Bacteria."
The United States produces over 8 billion broiler chickens per year. How many of these chickens infected with Campylobacter jejuni bacteria are making people sick? "The main implication is that Campylobacter is not always harmless to chickens. This rather changes our view of the biology of this nasty little bug," says Paul Wigley, according to the July 1, 2014 news release, "Foodborne bacteria can cause disease in some breeds of chickens after all." Wigley is with the Institute for Infection and Global Health at the University of Liverpool, an author on the study.
Campylobacter jejuni is the most frequent cause of foodborne bacterial gastroenteritis in the world and the Centers for Disease Control and Prevention estimate it affects approximately 1.3 million people per year in the United States. Chicken is the most common source of infections. Infection of chickens had previously not been considered to cause disease and the bacteria were thought to be part of the normal microbiota of the birds. You also may wish to check out the CDC article, "Campylobacter, General Information."
Chicken is the most common source of infections
In the study, Wigley and his colleagues experimentally infected birds from four commercial breeds of broiler chickens. They found that while levels of the bacteria in the intestines did not differ by breed, immune response and inflammation did, to the extent that one breed showed damage to the gut mucosa and developed diarrhea.
"Interestingly the breeds did not differ in the levels of bacteria we found in their intestines after infection, even when kept to normal slaughter age," says Wigley, according to the news release. "This suggests that chicken breed has little direct effect on the risk of Campylobacter entering the food chain but has a big effect on the health of the birds."
The most important finding, says Wigley, is that Campylobacter infection directly impacts broiler chicken health and welfare
The United States produces over 8 billion broiler chickens per year and the United Kingdom produces nearly a billion. As Campylobacter is common, or even endemic, in these industries then the scale of the impact on animal health is clear to see. "On the positive side, we now know that chickens produce a robust immune response to infection, which in the longer term may allow us to develop vaccines," says Wigley, according to the news release.
The Biotechnology and Biological Sciences Research Council (BBSRC) as well as a consortium of poultry producers, breeders and retailers funded teh research. mBio® is an open access online journal published by the American Society for Microbiology to make microbiology research broadly accessible. The focus of the journal is on rapid publication of cutting-edge research spanning the entire spectrum of microbiology and related fields. http://mbio.asm.org.
Animals, including fish, are smarter than people think. You also may be interested in news of another study, "Smarter than you think: Fish can remember where they were fed 12 days later." Another noteworthy study to peruse is "Cholesterol levels may regulate susceptibility to HIV infection."