Prevalence and enumeration of Escherichia coli O157:H7 and Salmonella in U.S. Abattoirs that process fewer than 1,000 head of cattle per day

Abstract

A significant portion (15 to 20%) of beef in the United States is produced in small beef processing plants that harvest fewer than 1,000 cattle per day. However, there are little data on the prevalence and levels of Escherichia coli O157:H7 and Salmonella in these processing plants. To address this lack of data, hides (n = 1,995) and carcasses (n = 1,995) of cattle at seven small processing plants located across the United States were analyzed for E. coli O157:H7 and Salmonella. Across all plants, hide prevalence of E. coli O157:H7 and Salmonella was 71 and 91%, respectively. Twelve percent of hides had E. coli 0157.H7 at enumerable levels (≥40 CFU/100 cm2), while 36% of hides had Salmonella at enumerable levels. Across all plants, the prevalence of E. coli O157:H7 on preevisceration carcasses was 33%, with 2% at an enumerable level (≥0.8 CFU/100 cm2). Across all plants, Salmonella prevalence on preevisceration carcasses was 58%, with 8% at an enumerable level. Significant plant-to-plant variations in levels and prevalence of pathogens on carcasses were detected. Reduced levels of pathogens on carcasses were noted among small processors that had incorporated a hide-directed intervention. The results obtained are comparable to those observed previously for larger processors, showing that smaller beef processors face and address the same challenges as do larger beef processors.