Reference | Ebner2000 (10166)

48 crossbred (Yorkshire-Landrace X Duroc) barrows and gilts used. A strain ofSalmonellaTyphimuriumcontaining a nalidixic acid resistance marker (SalmonellaTyphi-murium #4232, Animal Disease Control Center, Ames, Iowa) wasused as the inoculation strain. Nal-idixic acid was then included in the plating medium to excludegrowth of salmonellae other than the original inoculate that thepigs may have come in contact with during the course of thestudy. Pigs were inoculated orally and intranasally with 3 ml of the culture. Pigs were blocked bylitter, randomly assigned to one of four treatment groups, andplaced by group into separate pens resulting in a final populationof 12 pigs/pen. Treat-ments were initiated at 2 days postinoculation (DPI) and included(i) intramuscular injection of ceftiofur sodium (Naxcel; Pharmacia& Upjohn, Kalamazoo, Mich.) for 3 days followed by the inclu-sion of oxytetracycline (Terramycin; Pfizer, Groton, Conn.) at 100g/ton of feed; (ii) apramycin (Apralan; Elanco, Indianapolis, Ind.)at 150 g/ton of feed for 14 days followed by oxytetracycline at100 g/ton of feed; (iii) carbadox (Mecadox; Pfizer) at 50 g/ton offeed until pigs reached 35 kg, followed by oxytetracycline at 100g/ton of feed, and (iv) no antibiotics (control).

Fecal samples were collected on the dayof inoculation and at 2, 4, 7, 14, 21, 28, 42, 56, 70, and 84 DPI.Fecal samples were obtained by insertion of two nonabsorbableDacron swabs (Hardwood Products, Guilford, Minn.) into eachpig’s rectum

AST Method: None

Reference explicitly reports AST breakpoints: Uncertain

Reference reports using a MIC table: False