title: Control of Escherichia coli O157 on beef at 37, 22 and 4 °C by T5-, T1-, T4-and O1-like bacteriophages.
abstract: Efficacy of four bacteriophages (phages) and a cocktail for biocontrol of Escherichia coli O157 was assessed on beef samples stored at 4, 22 and 37 °C. Samples (3 × 3 × 1 cm) were contaminated with E. coli O157 (10(4) CFU/cm(2)) and treated with single phages: T5-like (T5), T1-like (T1), T4-like (T4) and O1-like (O1), or a cocktail at two titers: multiplicity of infection (MOI) = 1000 and MOI = 10. In contrast to previous studies, use of virucidal solution prevented over-estimation of phage efficacy. Irrespective of temperature and MOIs, T5 was most (P < 0.001) and O1 least (P < 0.05) effective for biocontrol of E. coli O157, with relative efficacy of other phages temperature dependent. At 4 °C, T1 (P < 0.05) and cocktail (P < 0.001) were more effective than T4. In contrast, T4 was equally (P = 0.08, at 37 °C) or less effective (P = 0.003, at 22 °C) than T5. Phages were more effective (P < 0.001) against E. coli O157 at warmer temperatures and high MOI. As the beef supply chain includes hours of storage or transport at temperatures near 4 °C, this study demonstrates phages could significantly reduce E. coli O157 during this period.
authors.affiliation: Inner Mongolia Agricultural University, College of Animal Science, Hohhot, Inner Mongolia, PR China; Agriculture and Agri-Food Canada, Lethbridge, AB, Canada.
authors.forename: H
authors.initials: H
authors.lastname: Liu
authors.affiliation: Alberta Agriculture and Rural Development, Lethbridge, AB, Canada.
authors.forename: Y D
authors.initials: YD
authors.lastname: Niu
authors.affiliation: Inner Mongolia Agricultural University, College of Animal Science, Hohhot, Inner Mongolia, PR China.
authors.forename: R
authors.initials: R
authors.lastname: Meng
authors.affiliation: South China Agricultural University, College of Veterinary Medicine, Guangzhou, Guangdong, PR China.
authors.forename: J
authors.initials: J
authors.lastname: Wang
authors.affiliation: Inner Mongolia Agricultural University, College of Animal Science, Hohhot, Inner Mongolia, PR China.
authors.forename: J
authors.initials: J
authors.lastname: Li
authors.affiliation: Public Health Agency of Canada, Guelph, ON, Canada.
authors.forename: R P
authors.initials: RP
authors.lastname: Johnson
authors.affiliation: Agriculture and Agri-Food Canada, Lethbridge, AB, Canada.
authors.forename: T A
authors.initials: TA
authors.lastname: McAllister
authors.affiliation: Alberta Agriculture and Rural Development, Lethbridge, AB, Canada. Electronic address: kim.stanford@gov.ab.ca.
authors.forename: K
authors.initials: K
authors.lastname: Stanford
mesh_terms: D000818:Animals; D017122:Bacteriophage T4 / Q000502:physiology; D061046:Biological Control Agents; D002417:Cattle; D003090:Coliphages / Q000502:physiology*; D004927:Escherichia coli Infections / Q000517:prevention & control; D019453:Escherichia coli O157 / Q000254:growth & development / Q000502:physiology*; D005516:Food Microbiology; D050296:Microbial Viability; D000069466:Red Meat / Q000382:microbiology* / Q000821:virology*; D013696:Temperature
chemical_list: D061046:Biological Control Agents
keywords: Bacteriophages; Escherichia coli O157; O1-like; T1-like; T4-like; T5-like