Reference | Jimnez.Belenguer_2016_AviaPath (10299)

Twenty-two one-day-old healthy Ross male chickens were obtained from a commercial hatchery. Chicks were labelled and randomly assigned to six groups of three and one with four chicks. Transmission of bacteria between groups was avoided by having a solid separation between pens. The control group with four chicks was kept untreated. The six remaining groups were treated with amoxicillin according to the manufacturer’s instructions. Chickens were kept in the experimental facilities from day of arrival (day 0) until day of slaughter (day 49) and they were weighed and treated with different doses (D) of amoxicillin: D1, 24 mg amoxicillin/kg body weight; D2, 12 mg amoxicillin/kg and D3, 8 mg amoxicillin/kg. Each dose was administered to two different groups. Dose administration was carried out with an oral syringe. The treatments (T) were administered over 3 days. Treatment one (T1) started on day 7, treatment two (T2) on day 21 and treatment three (T3) on day 35 of the chickens’ life. No other antimicrobial treatment was administered during the course of the experiment.

Four sample collections were carried out during the experimental period, immediately before administration of antibiotic doses. The first sampling was on day 0 on meconia, the second and third samplings took place on days 21 and 35. Samples were taken directly from the cloaca using a swab. The final sampling was on day 49 and samples were taken directly from the caecum after euthanasia with embutramide.

AST Method: Disk Diffusion

Reference explicitly reports AST breakpoints: True

Reference reports using a MIC table: False