Reference | Usui2014a (20027) (Excluded)

Fifteen healthy pigs 18 days of age were obtained from a single farm. The pigs were fed once daily with antimicrobial-free commercial pig feed and had free access to water. The Animal Ethical Committee and the Animal Care and Use Committee of the National Institute of Animal Health approved all animal experiments.Intramuscular administration with enrofloxacin is approved for 3 consecutive days at doses of 1.25–2.5 mg/kg body weight and 2.5–5 mg/kg body to treat enteritis and respiratory disease, respectively. Norfloxacin is approved for oral administration for 5 consecutive days at doses of 5–10 mg/kg body. Pigs were housed in individual pens for 9 days before treatment (day 1 [D1]). Pigs weighing 7.5–9.0 kg were randomly assigned to three groups of five pigs each as follows: (1) not treated with antimicrobials, (2) intramuscular administration of a dose of 5 mg enrofloxacin/kg of body weight/day, or (3) oral administration of a dose of 5 mg norfloxacin/kg of body weight/day from D1 to D5 (Table 1; Groups 1, 2, and 3). After evaluating the effect of FQ administration on the emergence of FQ-resistant bacteria, all five FQ-resistant Campylobacter-free pigs derived from the negative control group and one randomly selected pig derived from the enrofloxacin group, which harbored FQ-resistant Campylobacter, were evaluated for the effect of group housing on the spread of FQ-resistant Campylobacter (Table 1; Group 4). These pigs were housed in individual pens for 2 weeks from the end of the first test. Thereafter, they were housed in a same pen.

Fecal samples were recovered from pigs after anal stimulation before administration (at D-4), during administration (D1–D5), and after administration (D8, D11, D14, D17, D20, D23, and D26). Environmental samples were simultaneously collected from the ground, feed, and drinking water in the pen by using sterile cotton swabs.

AST Method: None

Reference explicitly reports AST breakpoints: False

Reference reports using a MIC table: False