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Recent research into feed processing and biosafety
The U.S. feed industry is under increased regulatory scrutiny as the Food Safety Modernization Act (FSMA) will soon require feed mills to have food safety plans with hazard analysis and controls. In addition to traditional physical and chemical hazards, biological hazards such as Salmonella and porcine epidemic diarrhea virus (PEDv) have also been associated with feed. Salmonella deaths from shell eggs in 2010 were traced to unsanitary conditions in layer houses and a feed mill, and Salmonella illnesses in humans were traced to contaminated dry dog food in 2012. More recently, feed has been proven to be one of the many vectors of PEDv transmission in the swine industry. Fortunately, there are solutions to minimize these potential feed pathogens. Interventional strategies to minimize biological hazards in feed can be categorized as thermal or non-thermal. Pathogen mitigation by thermal processing is relatively practical, but the time and temperature relationship required is dependent upon the pathogen, dose, and matrix. Additionally, steps must be taken to prevent recontamination of animal feed during cooling, load out, and transportation because thermal inactivation of pathogens occurs at a point in time, but has no sustained effects to prevent recontamination. Non-thermal mitigation strategies, such as the inclusion of chemical additives, typically retain some mitigation characteristics to some level to prevent recontamination. However, chemical mitigants may have drawbacks associated with worker safety, consumer acceptance, or regulatory approval. For example, commercial formaldehyde has been shown to be effective at mitigating PEDv in swine feed and protein meals, but it is only approved for use in animal feed for Salmonellacontrol. Again, the effectiveness of various chemical mitigants depends upon matrix and inclusion level. The feed industry has advanced its understanding of feed biosafety in recent years. Nevertheless additional research is needed to refine pathogen mitigation strategies to maximize effectiveness while simultaneously increasing practicality of implementation.
Keywords: biosafety, feed, PEDv, pathogen, Salmonella