Chapter 5 - Tracing Meat Products through the Production and Distribution Chain from Farm to Consumer

Abstract

This chapter deals with the application of genetic identification techniques to meat-producing animals. This approach assists in identification of the contributing source of a biological agent such as Escherichia coli O157:H7, bovine spongiform encephalopathy (BSE), Listeria monocytogenes, and Salmonella spp. The same approach is used to trace chemical contaminants such as dioxins, drugs, or hormone residues. This approach provides a platform to describe both the complexity of the meat supply chain and the role that genetic identification of the production animal can play in pinpointing the source of contamination and narrowing the scope of a product recall. A common theme during food safety incidents is the difficulty in following the source of contamination back through the processing and distribution chain. Tracing animals through these livestock production systems is aided by the identification of animals and the registration of premises. Identification may be individual or batch based and the technologies may be conventional numeric/alphanumeric tags, bar code tags, radio-frequency identification tags/transponders, tattoos, brands, biometrics, or genetic identification. Genetic identification is being used routinely, in clearly defined commercial contracts, to provide effective traceability of meat products, particularly pork and beef. The conceptual framework for these programs acts as a model for microbial forensics. In order to harness the individual-level identification afforded by genetic analysis, reference samples from the point of slaughter are required. The investigating authorities might access or mediate sampling of carcasses, but in the European case it would be relatively straightforward for officials currently sampling carcasses for BSE testing to be tasked with DNA sample collection.