Reference | Usui2014 (20028) (Excluded)

In this study, 15 healthy, 30-day-old pigs from a single farm were fed once daily with antimicrobial-free, commercial pig feed, and they 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 the animal experiments. Antimicrobial drugs were purchased as veterinary medical products. Erythromycin injection solution (5 g/100 ml erythromycin, injectable solution; Kyoritsu Seiyaku; Tokyo, Japan) was used for intramuscular administration. Tylosin phosphate (Nippon Formula Feed Manufacturing; Kanagawa, Japan) was used for oral administration of a feed additive. Intramuscular administration with erythromycin is approved at doses of 2–7 mg/kg of body weight to treat pneumonia, bronchitis and pharyngolaryngitis. Tylosin phosphate is approved for oral administration as a feed additive at doses of 44–110 g/ton of feed to treat pneumonia and bacterial diarrhoea. Pigs were housed in individual pens for 14 days before treatment initiation (day 1). They were randomly assigned to three groups of five pigs each, as follows: Group 1, pigs not treated with antimicrobials; Group 2, pigs treated by intramuscular administration with a standard therapeutic dose of 7 mg/kg of erythromycin per day for seven days; and Group 3, pigs treated orally with a standard therapeutic dose of 44 g/ton of tylosin for 14 days. These doses, administration routes and administration periods are commonly used by clinical veterinarians.

Faecal samples were collected on treatment days -14, 1, 5, 9, 15 and 22.

AST Method: None

Reference explicitly reports AST breakpoints: False

Reference reports using a MIC table: False