title: Prevalence of antimicrobial resistance in fecal generic Escherichia coil isolated in western Canadian beef herds. Part II--cows and cow-calf pairs.
abstract: The objective of this study was to describe antimicrobial resistance in fecal generic Escherichia coli isolated from cows and cow-calf pairs from western Canadian beef herds. Susceptibility testing was completed on 1555 E. coli isolates (n = 533 cows from 69 herds) harvested from fresh fecal samples in the spring of 2002, and 630 isolates (n = 105 cow-calf pairs from 10 herds) collected in the spring of 2003. Only 1 cow isolate was resistant to an antimicrobial classified by Health Canada as being of very high importance to human medicine. Resistance to at least 2 antimicrobials was detected in 7.1% of the 2002 cow isolates, in 3.4% of the 2003 cow isolates, and 23.2% of the 2003 calf isolates. In the cows, resistance to at least 1 antimicrobial was not associated with cow breed (P = 0.16), cow age (P = 0.14), or previous cow treatment (P = 0.56). In the calves, resistance to at least 1 antimicrobial was not predicted by whether or not its dam was resistant to at least 1 antimicrobial (P = 0.36).
authors.affiliation: Department of Large Animal Clinical Sciences, Western College of Veterinary Medicine, 52 Campus Drive, Saskatoon, Saskatchewan S7N 5B4. sheryl.gow@usask.ca
authors.forename: Sheryl P
authors.initials: SP
authors.lastname: Gow
authors.forename: Cheryl L
authors.initials: CL
authors.lastname: Waldner
authors.forename: Andrijana
authors.initials: A
authors.lastname: Rajić
authors.forename: Margaret E
authors.initials: ME
authors.lastname: McFall
authors.forename: Richard
authors.initials: R
authors.lastname: Reid-Smith
mesh_terms: D000367:Age Factors; D000818:Animals; D000831:Animals, Newborn; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002170:Canada / Q000453:epidemiology; D002417:Cattle; D002418:Cattle Diseases / Q000188:drug therapy* / Q000453:epidemiology / Q000382:microbiology; D015169:Colony Count, Microbial / Q000662:veterinary; D004305:Dose-Response Relationship, Drug; D024881:Drug Resistance, Bacterial; D024901:Drug Resistance, Multiple, Bacterial; D004926:Escherichia coli / Q000187:drug effects* / Q000302:isolation & purification; D004927:Escherichia coli Infections / Q000188:drug therapy / Q000453:epidemiology / Q000382:microbiology / Q000662:veterinary*; D005243:Feces / Q000382:microbiology*; D005260:Female; D008297:Male; D008826:Microbial Sensitivity Tests / Q000662:veterinary; D015995:Prevalence; D012307:Risk Factors; D012621:Seasons; D012737:Sex Factors
chemical_list: D000900:Anti-Bacterial Agents