title: Super shedding of Escherichia coli O157:H7 by cattle and the impact on beef carcass contamination.
abstract: Beef carcass contamination is a direct result of pathogen transfer from cattle hides harboring organisms such as enterohemorrhagic Escherichia coli. Hide contamination occurs from direct and indirect fecal contamination in cattle production and lairage environments. In each of these environments, individual animals shedding E. coli O157:H7 at high levels (>10(4) CFU/g of feces, hereafter referred to as "super shedders") can have a disproportionate effect on cattle hide and subsequent carcass contamination. It is not known what criteria must be met to cause an animal to shed at levels exceeding 10(4) CFU/g. Understanding the factors that play a role in super shedding will aid in minimizing or eliminating the super shedding population. Interventions that would prevent super shedding in the cattle population should reduce E. coli O157:H7 transmission in the production and lairage environments resulting in reduced risk of beef carcass contamination and a safer finished product.
authors.affiliation: U.S. Department of Agriculture, Agricultural Research Service, Roman L. Hruska U.S. Meat Animal Research Center, Clay Center, Nebraska 68933-0166, USA. terrance.arthur@ars.usda.gov
authors.forename: Terrance M
authors.initials: TM
authors.lastname: Arthur
authors.forename: Dayna M
authors.initials: DM
authors.lastname: Brichta-Harhay
authors.forename: Joseph M
authors.initials: JM
authors.lastname: Bosilevac
authors.forename: Norasak
authors.initials: N
authors.lastname: Kalchayanand
authors.forename: Steven D
authors.initials: SD
authors.lastname: Shackelford
authors.forename: Tommy L
authors.initials: TL
authors.lastname: Wheeler
authors.forename: Mohammad
authors.initials: M
authors.lastname: Koohmaraie
mesh_terms: D000818:Animals; D057138:Bacterial Shedding; D002417:Cattle / Q000382:microbiology*; D002418:Cattle Diseases / Q000382:microbiology / Q000635:transmission; D004927:Escherichia coli Infections / Q000382:microbiology / Q000635:transmission / Q000662:veterinary*; D019453:Escherichia coli O157 / Q000254:growth & development / Q000302:isolation & purification*; D005516:Food Microbiology; D008460:Meat / Q000382:microbiology*; D008462:Meat-Packing Industry