Agriculture researches are trying to figure out exactly how diseases move from cattle to humans by taking a closer look at the feedlot.

 

Calgary, Alta., Sept. 6, 2006: Agricultural researchers are tracking the movement of bacteria from cattle feedlots in a large-scale, high-tech project that has all the plot elements of popular television detective dramas.

"You could call what we're doing 'CSI: Feedlot," jokes Dr. Doug Inglis of Agriculture and Agri-Food Canada (AAFC), who leads the multi-institutional, four-year project.

The research involves a team of investigators, DNA tracing and a destructive and elusive pest. But in this case the focus is not a criminal. Rather, it's Campylobacter - a group of bacteria found in cattle intestines and shed in cattle feces.

Campylobacter species, particularly Campylobacter jejuni and Campylobacter coli, are one of the most common causes of acute diarrheal disease (campylobacteriosis) in humans throughout the world. But the connection between Campylobacter species originating in cattle and those infecting humans is unclear.

By tracing the movement of Campylobacter species - collectively referred to as "campylobacters" - from the feedlot, Inglis and colleagues will generate information that can be used to assess the threat to humans and to develop strategies for reducing that threat.

"Currently, poultry are thought to be the primary reservoir of Campylobacter species infecting humans," says Inglis. "However there are strong indications that cattle are a major source as well. We feel that campylobacters from beef cattle is an emerging issue that we have the opportunity to address in a proactive manner."

Inglis discusses the challenges and opportunities for this research in a new, "Perspectives on Beef Science" article, now available on the Meristem Land and Science Web site, www.meristem.com. Land and Science is a service featuring information on the sustainability of agriculture, food production and the environment. It is presented by Meristem Information Resources Ltd., in co-operation with partners in agriculture, food, environment and life sciences.

Molecular-based tracing tools have great potential to help strengthen the bio-security of Canada's beef industry, says Inglis. The current project includes components to assess bacteria at the feedlot level, including in various areas of the feedlot environment, in the surrounding environment, at the abattoir and in meat at the retail level. It also includes a human health component that includes assessing stool samples from patients suffering from gastroenteritis.

"The biggest challenge for this type of research is developing effective methods to identify, quantify and track the bacteria," says Inglis. "We recognized a new, more sophisticated approach was needed."

In a previous study, funded by the Canada Alberta Beef Industry Development Fund (CABIDF), Inglis and colleagues developed a series of tools based on Polymerase Chain Reaction (PCR), a molecular-based detection method.

"PCR" is far more advanced than traditional approaches, says Inglis. "This technology is commonly used in forensics to catch criminals, and it holds a lot of potential for investigating many types of human-pathogenic bacteria associated with cattle."

Meristem "Perspective" articles and reports are an ongoing series designed to bring to light various important perspectives on issues critical to sustainable agricultural, food and environmental systems. Development of the Campylobacter project article was supported by CABIDF.