EFFICACY OF AN AMOXICILLIN ORAL SOLUBLE POWDER (SURAMOX~(R) 50) IN THE TREATMENT OF NATURALLY OCCURRING INFECTIONS DUE TO ACTINOBACILLUS PLEUROPNEUMONIAE IN PIGS

摘要

In vitro activity of amoxicillin against Actinobacillus pleuropneumoniae has been described (1). A multicentre, controlled, and randomised study was performed in three pig herds in France and one pig herd in Belgium to assess the efficacy of an amoxicillin oral soluble powder administered either in drinking water or in liquid feed against naturally occurring infections due to Actinobacillus pleuropneumoniae. Criteria of inclusion were clinical signs and lesions of pleuropneumonia and confirmation ofA. pleiiropneumoniae infection from bacteriological or serological examinations. In each site pigs were randomly assigned to two groups. In group 1 a 50% based amoxicillin oral soluble powder (Suramox~(R) 50) was administered once per day. In group 2 a 10% based amoxicillin oral soluble powder was administered twice per day. Drugs were distributed via drinking water in sites Wl and W2 and via liquid feed in sites Fl and F2 in order to achieve an amoxicillin dosage regimen of 20 mg/kg/day from Day 0 (DO)to D4. In each site pigs of one pen per group were individually identified and weighed on DO. A standardised clinical examination was performed on identified pigs on D0, Dl, D3, D5, D10. Each clinical sign was scored from 0 to 3 : general status, cough,respiratory rate, nasal discharge, lameness. At least two pigs per site were necropsied before start of treatment. Each gross lesion was scored from 0 to 3 : pneumonia, pleuritis, pericarditis, arthritis. Bacteriological examinations were performed on necropsied pigs and from nasal swabs taken on 10 pigs on DO. In site W2 serological examinations against A. pleiiropneumoniae were also performed from blood samples of five pigs on D10 and D31 according to an ELISA technique. Mortality rates from DO to D10 were compared between groups by the chi-square test.Rectal temperature and total clinical score were compared between groups by a two-way repeated measures analysis of variance.