RESUMO
This study was carried out to compare the efficacy of two oral anti-microbials as metaphylactic medication to pigs inoculated with Actinobacillus pleuropneumoniae serotype 1. Forty-two pigs with an average weight of 22.64 kg were randomly assigned to three treatment groups: group F was given doses of 40 ppm of florfenicol, group E received 150 ppm of enrofloxacin and group C received no medication. Groups F and E received medicated feed 12 h before being inoculated and for 7 days after inoculation. All the pigs were inoculated by aerosol, with 2 x 10(7) CFU/ml of A. pleuropneumoniae serotype 1 each. The average body temperature was higher in group C than in groups E and F, between 12 and 96 h after inoculation (P < 0.05). No differences were found between groups F and E in respiration pattern, nasal secretion and general condition (P > 0.05): however, differences were found in group C for respiration pattern and general condition (P < 0.05), 12 h after inoculation. There was no mortality in groups F and E, whereas a 50% mortality was recorded in group C during the first 48 h after inoculation (P < 0.05). Necropsies and bacterial cultures were performed 12 days after inoculation. Lesions were observed in five pigs of group F (35.71%) with an average damage of 1.16%; in four pigs of group E (28.57%) with 1.24%; and in 13 animals in group C (92.85%) with 34.5% of affected lung tissue (P < 0.05). The infective agent was cultured from various organs of animals in groups F and C, but not from those in group E.
