title: A longitudinal study of feed contamination by European starling excreta in Ohio dairy farms (2007-2008).
abstract: The objectives of this study were to understand the temporal pattern of contamination of cattle feed by starling excrement on dairy farms and to evaluate the temporal pattern in recovering Escherichia coli O157:H7 or Salmonella in relation to the absolute mass of excrement recovered. A longitudinal study was conducted on 15 dairy farms in Ohio from July 2007 to October 2008. One open-topped tray filled with bird feed was placed near a cattle feeding site; bird excrement from the tray was weighed monthly for 12 consecutive months. Linear regression models with a random intercept for farm were computed to examine the association between the absolute weight of excrement recovered each month or the farm-specific standard score for weight of excrement, and month or season. Exact logistic regression was used to determine whether an association between recovering E. coli O157:H7 or Salmonella was present and the amount of excrement recovered and season. A spatial scan statistic was used to test for evidence of space-time clustering of excrement, based on the standard score for the weight of the excrement, among our study farms. A total of 5 of 179 excrement samples (2.79%) were positive for E. coli O157:H7 and 2 (1.12%) were positive for Salmonella. A significantly higher level of contamination with excrement was observed during the winter. The odds of recovering a pathogen increased with the amount of excrement recovered and decreased if the excrement was collected in the winter. A spatio-temporal cluster of contamination with excrement was detected. These findings provide basic information for future quantitative microbial risk assessments concerning the role of starlings in spreading enteric pathogens on dairy farms.
authors.affiliation: Department of Population Medicine, university of guelph, guelph, oN, N1g 2W1, Canada. Electronic address: gasmelas@uoguelph.ca.
authors.forename: G A
authors.initials: GA
authors.lastname: Medhanie
authors.affiliation: Department of Population Medicine, university of guelph, guelph, oN, N1g 2W1, Canada.
authors.forename: D L
authors.initials: DL
authors.lastname: Pearl
authors.affiliation: Department of Population Medicine, university of guelph, guelph, oN, N1g 2W1, Canada.
authors.forename: S A
authors.initials: SA
authors.lastname: McEwen
authors.affiliation: Department of Population Medicine, university of guelph, guelph, oN, N1g 2W1, Canada.
authors.forename: M T
authors.initials: MT
authors.lastname: Guerin
authors.affiliation: Department of Pathobiology, Ontario Veterinary College, University of Guelph, Guelph, ON, N1G 2W1, Canada.
authors.forename: C M
authors.initials: CM
authors.lastname: Jardine
authors.affiliation: Food Animal and Health Research Program, Ohio Agricultural Research and Development Center, The Ohio State University, Wooster 44691.
authors.forename: J
authors.initials: J
authors.lastname: Schrock
authors.affiliation: Food Animal and Health Research Program, Ohio Agricultural Research and Development Center, The Ohio State University, Wooster 44691.
authors.forename: J T
authors.initials: JT
authors.lastname: LeJeune
mesh_terms: D000821:Animal Feed / Q000032:analysis* / Q000382:microbiology; D000818:Animals; D002417:Cattle; D002418:Cattle Diseases / Q000453:epidemiology* / Q000382:microbiology; D003612:Dairying; D004927:Escherichia coli Infections / Q000453:epidemiology / Q000382:microbiology / Q000662:veterinary*; D019453:Escherichia coli O157 / Q000302:isolation & purification; D005243:Feces / Q000382:microbiology; D005516:Food Microbiology; D016015:Logistic Models; D008137:Longitudinal Studies; D009820:Ohio / Q000453:epidemiology; D012475:Salmonella / Q000302:isolation & purification; D012481:Salmonella Infections, Animal / Q000453:epidemiology* / Q000382:microbiology; D012621:Seasons; D046749:Starlings
keywords: European starling; fecal weight; month; multilevel