Written by Michael Wilson
June 3, 2008
Consumer protection from food-borne illnesses is an ever-growing concern for our society. Each year, there are a growing number of outbreaks of human illness from food contaminated by biological pathogens. Salmonella and E. coli are among the most publicized culprits of these outbreaks and most often linked to the consumption of farm produce and undercooked meat. Although pathogens in meat products can be eliminated by proper cooking, minimizing the risk of exposure of farm animals to these pathogens is one essential step towards averting potential outbreaks. In terms of food safety on a farm, the roles of water, animal waste, and food harvesting and handling methods have been investigated in other studies. Although the potential impact of wild animals has been considered as a factor for food-borne pathogen contamination, no study has quantitatively assessed the risks of transmission from wild birds to farm livestock.
The Center for Conservation Biology (CCB) has entered into a 2-year cooperative study funded by the United Stated Department of Agriculture that also brings together food safety science experts from Virginia State University (VSU) and farm management researchers at the University of Maryland Eastern Shore (UMES) to investigate the factors associated with the transmission of pathogens from wild birds to farm animals. The scope of this project spans the entire domain of food pathogen risk analysis by scientifically integrating risk assessment and risk management. In other words, this study not only evaluates the rate of pathogen transmission from birds to farm animals, but also how farms may be properly managed to reduce the risk of transmission.
Farm raised populations of sheep and goats managed at small ruminant pastures and laboratories of VSU and UMES and natural populations of birds present at each of these areas provide ideal study subjects to conduct such a risk analysis. We believe that reducing the risk of pathogen transmission from birds to farm animals can be achieved by eliminating items that specifically attract birds to livestock-use areas. Removing attractors such as leftover animal feed or preventing birds from using animal watering containers are the two best examples that can be experimentally controlled for analysis. During the spring and fall, CCB personnel are quantifying the space use of wild birds in farm conditions to quantify the relevant interaction with feeding, watering, and loafing areas of farm animals between farms that are managed with and without items that attract birds. We also capture these bird populations so we can collect waste that will be screened for the presence of commonly known and very harmful pathogens such as Salmonella, Campylobacter, and E. coli at VSU laboratories. Researchers from VSU and UMES are concurrently sampling livestock populations for the presence, timing, and extent of these pathogens to examine the frequency of infection between farms that attract birds and farms that do not attract birds. It is the hope of all researchers involved in this study that the results will broaden our knowledge of food safety by managing the risk factors associated with feeding livestock that result in pathogen transmission from bird populations.