Reference | 525E3ZBP (101)

The objectives were to examine the effect of ceftiofur use, ceftiofur cessation, and replacement with lincomycinspectinomycin at the hatchery on the proportion of samples with E. coli possessing the ESBL/AmpC genes blaCMY-2, blaSHV, blaOXA, blaCTX-M, and blaTEM and on the antimicrobial resistance profiles of these isolates in young chicks, broilers, and breeders of an integrated pyramid.

Two vertical samplings of meat chickens of an integrated pyramid in the province of Quebec in Canada were made. The first sampling period was between March and May 2014, when chicks (n 24 broiler flocks) were routinely receiving 0.08 to 0.2 mg of ceftiofur per egg as an in ovo injection (32, 33). The second sampling was done between June and October 2015, 1 year after preventive administration of ceftiofur at the hatchery had ceased

AST Method: Disk Diffusion

Reference explicitly reports AST breakpoints: None

Reference reports using a MIC table: None