Duration of efficacy of ceftiofur crystalline free acid sterile suspension against clinical disease in grower pigs challenged with <i>Actinobacillus pleuropneumoniae</i>

Materials and methods: One hundred and ninety male piglets were blocked by weight and randomly assigned to 19 pens of 10 animals each, with three pens randomly assigned to each of six treatments. Pigs were challenged with A pleuropneumoniae at 7 to 8 weeks old (Day 0). Groups 1 through 5 were treated with a single intramuscular dose of CCFA-SS (5 mg ceftiofur equivalents per kg body weight) on Days -13, -10, -7, -4, and -1, respectively. Group 6 pigs were challenged, untreated controls. A single pen of 10 unchallenged, untreated pigs acted as sentinels. The primary variable was removal rate (percent of pigs per pen that died or were euthanized because of severe illness by Day 9). Ancillary variables included demeanor and respiratory index scores, rectal temperature, and feed intake.