Organic or Antibiotic-Free Labeling Does Not Impact the Recovery of Enteric Pathogens and Antimicrobial-ResistantEscherichia colifrom Fresh Retail Chicken

Abstract

We investigated the implied health benefits of retail chicken breast labeled as "organic" or "antibiotic-free" when compared to conventional products based on frequency of contamination by Salmonella spp., Campylobacter spp., and coliform bacteria resistant to fluoroquinolones, extended-spectrum cephalosporins, or carbapenems. We purchased 231 prepackaged chicken breasts from 99 grocery stores representing 17 retail chains in Ohio, Michigan, and Pennsylvania from June to September 2012. Ninety-six (41.5%) packages were labeled "antibiotic free" and 40 (17.3%) were labeled "organic," with the remaining 95 (41.1%) making neither label claim. Salmonella were recovered from 56 (24.2%) packages, and the recovery rate was not different between product types. Five percent of packages contained Salmonella carrying the extended-spectrum cephalosporin resistance gene bla(CMY-2), representing 21.4% of Salmonella isolates. Campylobacter spp. were recovered from 10.8% of packages, with observed recovery rates similar for the three product types. Using selective media, we recovered Escherichia coli harboring bla(CMY-2) from over half (53.7%) of packages, with similar recovery rates for all product types. In addition, we recovered E. coli carrying bla(CTX-M) from 6.9% of packages, and E. coli with QRDR mutations from 8.2% of packages. Fluoroquinolone-resistant E. coli recovered using selective media were more common (p<0.05) in conventional (18.9%) compared to organic (0) and antibiotic-free (2.1%) packages. Our results indicate that, regardless of product type, fresh retail chicken breast is commonly contaminated with enteric pathogens associated with foodborne illness and commensal bacteria harboring genes conferring resistance to critically important antimicrobial drugs.

Extraintestinal Pathogenic and Antimicrobial-Resistant Escherichia coli, Including Sequence Type 131 (ST131), from Retail Chicken Breasts in the United States in 2013

“…In both the latter study and the present one, the absence of a protective effect of "all natural" and/or "no antibiotics" labeling suggests that such labels may not accurately reflect the actual antibiotic exposure of the source chickens. Alternatively, specific aspects of organic production, apart from its required absence of antibiotic use in chicks after the first day of life, may underlie the observed protective effect of the "organic" label claim against resistance, as documented here and by Mollenkopf et al (6).…”

“…Previous studies, including several to which some of the authors of the present study contributed, have documented the presence of ExPEC and antimicrobial-resistant E. coli isolates in retail chicken, turkey, beef, and pork products (5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19). Novel features of the present study include its extensive geographic range (previous studies based in the United States have been limited to four or fewer states [6,7,10]), its comparatively recent sampling frame (2013; the most recent similar study based in the United States was from 2012 [6]), and the extensive phylogenetic and clonal analysis performed on these isolates.…”

“…Novel features of the present study include its extensive geographic range (previous studies based in the United States have been limited to four or fewer states [6,7,10]), its comparatively recent sampling frame (2013; the most recent similar study based in the United States was from 2012 [6]), and the extensive phylogenetic and clonal analysis performed on these isolates. The clonal analysis showed, uniquely, an appreciable representation of E. coli ST131 isolates, albeit with the ST131-H22 clonal subset and not the pandemic ST131-H30 lineage that is the main cause of the current surge in fluoroquinolone resistance and extended-spectrum beta-lactamase production among human clinical E. coli isolates (4,26).…”

“…However, they also are commonly contaminated with antimicrobial-resistant E. coli and ExPEC strains, potentially posing an added risk to consumers (5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20). Previous market surveys have identified such E. coli isolates to be contaminants of retail chicken products from a limited range of sites within the United States (7,10,(12)(13)(14)(15)(16)(17)19).…”

Sustainability of livestock production systems : a comparing conventional and organic livestock husbandry

“…Van Overbeke et al (2006) found significantly higher prevalence in cecum (p=0.024) and duodenum (p=0.036) samples from organic compared to conventional broilers, but no difference in gastrointestinal tract prevalence. On retail level, two studies Mollenkopf et al, 2014) did not find a significant difference (p>0.05) and two studies (Cui et al, 2005;Hardy et al, 2013) did not mention significance levels.…”