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ARS Home » Plains Area » Clay Center, Nebraska » U.S. Meat Animal Research Center » Meat Safety and Quality » Research » Publications at this Location » Publication #410275
Research Project: Holistic Tactics to Advance the Microbiological Safety and Quality of the Red Meat Continuum

Location: Meat Safety and Quality

Title: Proportions and serogroups of enterohemorrhagic Shiga Toxin-producing Escherichia coli in feces of fed and cull beef and cull dairy cattle at harvest

Author
item Bosilevac, Joseph - Mick
item KATZ, TATUM - Orise Fellow
item Arthur, Terrance
item Kalchayanand, Norasak - Nor
item Wheeler, Tommy

Submitted to: Journal of Food Protection
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/2/2024
Publication Date: 4/8/2024
Citation: Bosilevac, J.M., Katz, T.S., Arthur, T.M., Kalchayanand, N., Wheeler, T.L. 2024. Proportions and serogroups of enterohemorrhagic Shiga Toxin-producing Escherichia coli in feces of fed and cull beef and cull dairy cattle at harvest. Journal of Food Protection. 87(6). Article 100273. https://doi.org/10.1016/j.jfp.2024.100273.
DOI: https://doi.org/10.1016/j.jfp.2024.100273

Interpretive Summary: Shiga toxin producing E coli (STEC) can cause very severe or life threatening disease if they are consumed. Cattle carry STEC and the STEC may contaminate beef during harvest and processing. In addition, cattle harvested for beef are raised in different production systems: feedlots, dairies, or beef herds. This work examined how each production system influenced the amount and type of STEC carried by cattle when they are harvested. Nearly all cattle from each production system carried STEC, but feedlot cattle carried more severe disease related STEC than cull dairy cattle, which carried more than cull beef cattle. Understanding how different STEC populate different production systems can help design better risk management strategies.

Technical Abstract: Cattle are considered a primary reservoir of Shiga toxin (stx)- producing Escherichia coli that cause enterohemorrhagic disease (EHEC), and contaminated beef products are one vehicle of transmission to humans. However, animals entering the beef harvest process originate from differing production systems: feedlots, dairies, and beef breeding herds. The objective of this study was to determine if fed cattle, cull dairy, and or cull beef cattle carry differing proportions and serogroups of EHEC at harvest. feces were collected via rectoanal mucosal swabs (RAMSs) from 1,039 fed cattle, 1,058 cull dairy cattle, and 1,018 cull beef cattle at harvest plants in seven U.S. states (CA, GA, NE, PA, TX, WA, and WI). The proportion of the stx gene in feces of fed cattle (99.04%) was not significantly different (P > 0.05) than in the feces of cull dairy (92.06%) and cull beef (91.85%) cattle. When two additional factors predictive of EHEC (intimin and ecf1 genes) were considered, EHEC was significantly greater (P < 0.05) in fed cattle (77.29%) than in cull dairy (47.54%) and cull beef (38.51%) cattle. The presence of E. coli O157:H7 and five common non-O157 EHEC of serogroups O26, O103, O111, O121, and O145 was determined using molecular analysis for single nucleotide polymorphisms (SNPs) followed by culture isolation. SNP analysis identified 23.48%, 17.67%, and 10.81% and culture isolation confirmed 2.98%, 3.31%, and 3.00% of fed, cull dairy, and cull beef cattle feces to contain one of these EHEC, respectively. The most common serogroups confirmed by culture isolation were O157, O103, and O26. Potential EHEC of fourteen other serogroups were isolated as well, from 4.86%, 2.46%, and 2.01% of fed, cull dairy, and cull beef cattle feces, respectively; with the most common being serogroups O177, O74, O98, and O84. The identification of particular EHEC serogroups in different types of cattle at harvest may offer opportunities to improve food safety risk management.