Factors associated with cross-contamination of hides of Scottish cattle by Escherichia coli O157

Mather, A.E., Reid, S.W.J., McEwen, S.A., Ternent, H.E., Reid-Smith, R.J., Boerlin, P., Taylor, D.J., Steele, W.B., Gunn, G.J. and Mellor, D.J. (2008) Factors associated with cross-contamination of hides of Scottish cattle by Escherichia coli O157. Applied and Environmental Microbiology, 74(20), pp. 6313-6319. (doi: 10.1128/AEM.00770-08)

Abstract

The putative source of hide contamination for 236 cattle in Scotland followed from the farm through to slaughter was determined using phage and verocytotoxin type data. The majority of cattle (84%) were found to have subtypes of Escherichia coli O157 on their hide that had not been found previously in any animal from the farm of origin, strongly suggesting that contamination occurred once animals had left the farm of origin. Using logistic regression analysis, several variables and factors were found to be strongly associated (P < 0.01) with cross-contamination of cattle hides at the univariate level; commercial transport to slaughter, transport with other animals, use of a crush, line automation, and increasing slaughterhouse throughput were all risk factors, while feeding hay in lairage, processing an animal earlier in a slaughter cohort, and cleaning the landing area poststunning were protective. In the multivariable model, with the slaughterhouse and the farm group included as random effects, factors associated with the cross-contamination of cattle hides were identified. Transport to the slaughterhouse by a commercial hauler had a borderline-significant association with increased odds of an animal having a cross-contaminated hide (odds ratio [OR] [95% confidence interval {CI}] = 5.7 [0.99, 33.0]; P = 0.05). At the slaughterhouse, providing hay to cattle waiting in lairage (OR [95% CI] = 0.04 [< 0.01, 1.04]; P = 0.05) and cleaning the landing area (OR [95% CI] = 0.03 [< 0.01, 1.15]; P = 0.06) also had a borderline-significant association with decreased odds of an animal having a cross-contaminated hide. Although the prevalence of carcass contamination remains very low, targeted intervention at the preslaughter stage may have the potential to reduce further the risk to public health

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Mellor, Professor Dominic and Taylor, Prof David and Steele, Mr William and Reid, Professor Stuart
• Authors: Mather, A.E., Reid, S.W.J., McEwen, S.A., Ternent, H.E., Reid-Smith, R.J., Boerlin, P., Taylor, D.J., Steele, W.B., Gunn, G.J., and Mellor, D.J.
• College/School: College of Medical Veterinary and Life Sciences > School of Biodiversity, One Health & Veterinary Medicine
• Journal Name: Applied and Environmental Microbiology
• Publisher: American Society for Microbiology
• ISSN: 0099-2240
• ISSN (Online): 1098-5336
• Published Online: 22 August 2008