title: Age-related decline in carriage of ampicillin-resistant Escherichia coli in young calves.
abstract: The presence of ampicillin-resistant Escherichia coli (Amp(r) E. coli) in the fecal flora of calves was monitored on a monthly basis in seven cohorts of calves. Calves were rapidly colonized by Amp(r) E. coli, with peak prevalence in cohort calves observed in the 4 months after the calves were born. The prevalence of calves yielding Amp(r) E. coli in cohorts consistently declined to low levels with increasing age of the calves (P < 0.001).
authors.affiliation: Centre for Tropical Veterinary Medicine, Roayl (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush Veterinary Centre, Roslin, Midlothian, United Kingdom. Deborah.Hoyle@ed.ac.uk
authors.forename: Deborah V
authors.initials: DV
authors.lastname: Hoyle
authors.forename: Darren J
authors.initials: DJ
authors.lastname: Shaw
authors.forename: Hazel I
authors.initials: HI
authors.lastname: Knight
authors.forename: Helen C
authors.initials: HC
authors.lastname: Davison
authors.forename: Michael C
authors.initials: MC
authors.lastname: Pearce
authors.forename: J Chris
authors.initials: JC
authors.lastname: Low
authors.forename: George J
authors.initials: GJ
authors.lastname: Gunn
authors.forename: Mark E J
authors.initials: ME
authors.lastname: Woolhouse
mesh_terms: D000375:Aging; D000668:Ampicillin Resistance; D000818:Animals; D002353:Carrier State / Q000382:microbiology / Q000662:veterinary*; D002417:Cattle; D002418:Cattle Diseases / Q000382:microbiology*; D004926:Escherichia coli / Q000187:drug effects / Q000302:isolation & purification*; D004927:Escherichia coli Infections / Q000382:microbiology / Q000662:veterinary; D005243:Feces / Q000382:microbiology*; D010403:Penicillin Resistance