G. Lakkakis, Ε. Mpourtzi-Chatzopoulou, Ν. Iliadis, S. Lekkas, S. K. Kyriakidis

In this study the participation of Pasteurella spp in swine pneumonia was investigated. Also the species and the serotype of the microorganism involved in the pulmonary pasteurellosis was determined. Finally the sensitivity of Pasteurella to different antibiotics, as well as its participation in weight gain of fattening pigs was checked. The investigation was carried out in an industrial pig farm. A total of 376 piglets, divided in three groups A,B,C were used. Out of the 172 slaughtered pigs of the experimental group A, pulmonary pasteurellosis was observed in 86 (50%), whereas only in 31 (37.3%) out of the 83 of the group B and 56 (46.2%) out of the 121 ones of the group C. From the lung samples with macroscopic lesions of pasteurellosis only Pasteurella multocida was isolated (93.06%). 18 lungs, which had not macroscopic lesions of pasteurellosis, was examined microscopically. All samples were negative for Pasteurella multocida. The 161 Pasteurella multocida isolated strains were serotyped. The 155 of them were of serotype A and 6 of serotype A and D. The sensitivity of 60 Pasteurella multocida isolates was investigated against 8 antibiotics. These strains were sensitive to chloramphenicol (100%), gentamycin (100%), kanamycin (98,3%), tetracycline (98,3%), sulfamethoxazole (96,6%) and erythromycin (95%). Sensitivity to streptomycin was low (13,3%). Al strains were resistant to ampicillin. Thirty samples of lungs with macroscopic lesions of pasteurellosis were examined histologically. Lesions of enzootic pneumonia with complication of fibrinous pneumonia were found in all of them. The average weight loss of slaughtered pigs with pasteurellosis, was 9.9% in the first experimental group, 11% in the second and 17.4% in the third one. These weight loss values were statistically different (P<0.001) in comparison with those of non infected pigs.