title: Longitudinal study of Escherichia coli O157:H7 in a beef cattle feedlot and role of high-level shedders in hide contamination.
abstract: The objectives of the study described here were (i) to investigate the dynamics of Escherichia coli O157:H7 fecal and hide prevalence over a 9-month period in a feedlot setting and (ii) to determine how animals shedding E. coli O157:H7 at high levels affect the prevalence and levels of E. coli O157:H7 on the hides of other animals in the same pen. Cattle (n = 319) were distributed in 10 adjacent pens, and fecal and hide levels of E. coli O157:H7 were monitored. When the fecal pen prevalence exceeded 20%, the hide pen prevalence was usually (25 of 27 pens) greater than 80%. Sixteen of 19 (84.2%) supershedder (>10(4) CFU/g) pens had a fecal prevalence greater than 20%. Significant associations with hide and high-level hide (>/=40 CFU/100 cm(2)) contamination were identified for (i) a fecal prevalence greater than 20%, (ii) the presence of one or more high-density shedders (>/=200 CFU/g) in a pen, and (iii) the presence of one or more supershedders in a pen. The results presented here suggest that the E. coli O157:H7 fecal prevalence should be reduced below 20% and the levels of shedding should be kept below 200 CFU/g to minimize the contamination of cattle hides. Also, large and unpredictable fluctuations within and between pens in both fecal and hide prevalence of E. coli O157:H7 were detected and should be used as a guide when preharvest studies, particularly preharvest intervention studies, are designed.
authors.affiliation: U.S. Department of Agriculture, Agricultural Research Service, Roman L. Hruska U.S. Meat Animal Research Center, Clay Center, NE 68933-0166, USA. terrance.arthur@ars.usda.gov
authors.forename: Terrance M
authors.initials: TM
authors.lastname: Arthur
authors.forename: James E
authors.initials: JE
authors.lastname: Keen
authors.forename: Joseph M
authors.initials: JM
authors.lastname: Bosilevac
authors.forename: Dayna M
authors.initials: DM
authors.lastname: Brichta-Harhay
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: Xiangwu
authors.initials: X
authors.lastname: Nou
authors.forename: Mohammad
authors.initials: M
authors.lastname: Koohmaraie
mesh_terms: D000821:Animal Feed; D000822:Animal Husbandry; D000818:Animals; D002417:Cattle / Q000382:microbiology*; D015169:Colony Count, Microbial; D019453:Escherichia coli O157 / Q000302:isolation & purification*; D005243:Feces / Q000382:microbiology; D005260:Female; D005506:Food Contamination / Q000517:prevention & control; D005516:Food Microbiology; D016015:Logistic Models; D008137:Longitudinal Studies; D008297:Male; D008460:Meat / Q000382:microbiology*; D008954:Models, Biological; D012621:Seasons; D012867:Skin / Q000382:microbiology; D012988:Soil Microbiology
references.citation: J Dairy Sci. 2001 Aug;84(8):1856-62
references.pmid: 11518311
references.citation: Appl Environ Microbiol. 2003 May;69(5):2444-7
references.pmid: 12732509
references.citation: Proc Natl Acad Sci U S A. 2006 Jan 17;103(3):547-52
references.pmid: 16407143
references.citation: Foodborne Pathog Dis. 2008 Apr;5(2):183-91
references.pmid: 18407757
references.citation: J Appl Microbiol. 1999 Dec;87(6):867-76
references.pmid: 10664910
references.citation: J Food Prot. 2007 May;70(5):1076-9
references.pmid: 17536663
references.citation: J Appl Microbiol. 2007 Nov;103(5):1657-68
references.pmid: 17953577
references.citation: Nat Rev Microbiol. 2005 Jul;3(7):529-36
references.pmid: 15995653
references.citation: Epidemiol Infect. 2006 Feb;134(1):131-42
references.pmid: 16409660
references.citation: Appl Environ Microbiol. 2004 Jan;70(1):377-84
references.pmid: 14711666
references.citation: J Food Prot. 2005 Jan;68(1):6-10
references.pmid: 15690797
references.citation: J Food Prot. 2007 Feb;70(2):280-6
references.pmid: 17340859
references.citation: Nat Rev Microbiol. 2008 Dec;6(12):904-12
references.pmid: 19008890
references.citation: J Food Prot. 2007 Nov;70(11):2568-77
references.pmid: 18044436
references.citation: J Food Prot. 2004 Apr;67(4):646-50
references.pmid: 15083713
references.citation: J Food Prot. 2005 Feb;68(2):265-72
references.pmid: 15726967
references.citation: J Food Prot. 2003 Nov;66(11):1972-7
references.pmid: 14627271
references.citation: Appl Environ Microbiol. 2008 Oct;74(20):6289-97
references.pmid: 18723661
references.citation: Appl Environ Microbiol. 2005 Jan;71(1):93-7
references.pmid: 15640175
references.citation: Am J Vet Res. 2000 Nov;61(11):1375-9
references.pmid: 11108182
references.citation: J Appl Microbiol. 2004;97(5):1045-53
references.pmid: 15479421
references.citation: J Food Prot. 2004 Nov;67(11):2391-6
references.pmid: 15553618
references.citation: J Food Prot. 2008 Mar;71(3):648-52
references.pmid: 18389717
references.citation: J Food Prot. 2004 Apr;67(4):658-65
references.pmid: 15083715
references.citation: Appl Environ Microbiol. 2003 Jan;69(1):542-7
references.pmid: 12514039
references.citation: J Food Prot. 2003 Nov;66(11):2005-9
references.pmid: 14627275
references.citation: Epidemiol Infect. 2004 Apr;132(2):291-5
references.pmid: 15061504
references.citation: Appl Environ Microbiol. 2007 Mar;73(5):1563-8
references.pmid: 17220263
references.citation: J Food Prot. 2004 Dec;67(12):2651-6
references.pmid: 15633666
references.citation: Can Vet J. 2001 Sep;42(9):714-20
references.pmid: 11565371