Spread of marker bacteria from the hides of cattle in a simulated livestock market and at an abattoir

• Published in: Journal of food protection Vol. 67; no. 11; pp. 2397 - 2402
• Main Authors: COLLIS, V. J, REID, C.-A, HUTCHISON, M. L, DAMES, M. H, WHEELER, K. P. A, SMALL, A, BUNCIC, S
• Format: Journal Article
• Language: English
• Published: Des Moines, IA International Association of Milk, Food and Environmental Sanitarians 01.11.2004
• Subjects: Abattoirs; Animal productions; Animals; Biological and medical sciences; Biomarkers - analysis; Cattle; Cattle Diseases - microbiology; Cattle Diseases - transmission; Colony Count, Microbial; Escherichia coli; Food Contamination - analysis; Food industries; Food Microbiology; Fundamental and applied biological sciences. Psychology; Meat and meat product industries; Pseudomonas fluorescens; Skin - microbiology; Terrestrial animal productions; Vertebrates; Meat animals; Farming animal; Skin take off; Transmission; Meat product; Bacteria; Markets; Marker; Slaughter; Biological contamination; Slaughterhouse
• ISSN: 0362-028X; 1944-9097
• DOI: 10.4315/0362-028X-67.11.2397

The spread of microbial contamination on the hides of beef was investigated at two stages in the meat chain: (i) in a simulated livestock market ("the market") using 33 animals, and (ii) in the unloading-to-skinning area of a commercial abattoir using 18 animals. At both stages, harmless bacterial markers (nalidixic acid-resistant Escherichia coli K-12; rifampicin- and nalidixic acid-resistant Pseudomonas fluorescens; and a tetracycline-resistant E. coli) were inoculated on the hides of a small number of selected animals, and their transfer to other animals and the environment was examined. At the market, the initial prevalence of animals positive for the hide markers (9.1% in each phase) introduced in the presale pen, sale ring, and postsale pen changed to 39.4, 15.1, and 54.5%, respectively, by the end of the market process. In addition, widespread contamination of the market environment with the hide markers was observed. At the abattoir, the initial prevalence of animals positive for the hide marker (11.1%) inoculated at unloading increased to 100% (hide before skinning) and 88.8% (skinned carcass). In addition, another marker inoculated on environmental surfaces in lairage pens, races, and stunning box was detected on 83.3% (hide before skinning) and 88.8% (skinned carcass). These results, although obtained with a relatively small number of animals, demonstrate that both the livestock market process and the unloading-to-skinning process at abattoirs can facilitate the extensive spread of microbial contamination on hides not just within, but also between, batches of animals.