Submitted to: Foodborne Pathogens and Disease
Publication Type: Peer reviewed journal
Publication Acceptance Date: 10/1/2004
Publication Date: 12/1/2004
Citation: Davies, P.R., Hurd, H.S., Funk, J.A., Cray, P.J., Jones, F.T. The role of contaminated feed in the epidemiology and control of salmonella enterica in pork production. Foodborne Pathogens and Disease. 1(4):202-215. 2004. Interpretive Summary: Salmonella is a zoonotic pathogen which can be transferred from animals to humans, most often through consumption of contaminated food. Infection with Salmonella can cause mild to severe gastroenteritis in humans while infection in food animals is often without clinical signs of disease. Contaminated feed is a recognized source of Salmonella infection of food animals. This paper describes the extent of Salmonella contamination of animal feed in the United States and discusses the pros and cons of establishing a zero tolerance policy for Salmonella in animal feeds. These data are necessary to enable a more informed debate among scientists, commodity groups, government regulators, and animal industry personnel on the feasibility and likely efficacy of enforcing a zero tolerance policy for Salmonella and as a means to reduce the incidence of human salmonellosis.
Technical Abstract: Contaminated feed is a recognized source of Salmonella infection of food animals and regulations to control Salmonella contamination of animal feed have existed in some countries for decades. The impact of reducing Salmonella contamination of animal feeds on the risk of human foodborne salmonellosis is difficult to assess, and is likely to vary among food animal industries. In the context of U.S. pork production, factors that may attenuate or negate the impact (on public health) of regulatory interventions to control Salmonella in commercial feed include widespread use of on-farm mixing of swine feed; incomplete decontamination of feed during processing; post-processing contamination of feed at feed mills or in transportation or on-farm storage; the multitude of nonfeed sources of Salmonella infection; an apparently high risk of post-farm infection in lairage; and post-harvest sources of contamination. A structured survey of the extent of Salmonella contamination of animal feed in the United States is necessary to enable more informed debate on the feasibility and likely efficacy of enforcing a Salmonella negative standard for animal feeds to reduce the incidence of human salmonellosis.