title: Effects of suspension in emulsified wiener or incubation in wiener packages on the virulence of Listeria monocytogenes Scott A in intragastrically inoculated A/J mice.
abstract: Several outbreaks of listeriosis have been associated with contamination of wieners and other ready-to-eat meat products. In this study, we addressed the question of whether emulsification in, or growth on, wieners triggers a response in the listerial cells that makes them more virulent or protects them against the harsh environment of the gastrointestinal tract in mice. Our results indicate that Listeria monocytogenes Scott A grows poorly, if at all, in one brand of commercially prepared wieners inoculated with 5 x 10(3) to 5 x 10(6) CFU per package and incubated at 15 degrees C. Neither L. monocytogenes Scott A emulsified in a slurry of homogenized wieners nor recovered from wiener package fluid after a 7-day incubation at 15 degrees C were more virulent when inoculated into the stomachs of A/J mice than L. monocytogenes Scott A grown in brain heart infusion broth. These findings suggest that the ability of L. monocytogenes Scott A to cause systemic infection following introduction into the gastrointestinal tract was not improved by incubation with wieners or suspension in a meat matrix.
authors.affiliation: Department of Pathobiological Sciences, School of Veterinary Medicine, and Food Research Institute, College of Agriculture and Life Sciences, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA.
authors.forename: Nancy G
authors.initials: NG
authors.lastname: Faith
authors.forename: Mark L
authors.initials: ML
authors.lastname: Tamplin
authors.forename: Darrell
authors.initials: D
authors.lastname: Bayles
authors.forename: John B
authors.initials: JB
authors.lastname: Luchansky
authors.forename: Charles J
authors.initials: CJ
authors.lastname: Czuprynski
mesh_terms: D000818:Animals; D015169:Colony Count, Microbial; D003257:Consumer Product Safety; D004195:Disease Models, Animal; D004655:Emulsions; D005260:Female; D005516:Food Microbiology; D006801:Humans; D008089:Listeria monocytogenes / Q000254:growth & development / Q000472:pathogenicity*; D008088:Listeriosis / Q000382:microbiology*; D008461:Meat Products / Q000382:microbiology*; D051379:Mice; D013696:Temperature; D014774:Virulence
chemical_list: D004655:Emulsions