OCCURRENCE OF SEROTYPES OF ACTINOBACILLUS-PLEUROPNEUMONIAE BIOTYPE-1 IN HUNGARY AND ITS PRACTICAL IMPORTANCE

Of the lungs of 197 fattening pigs, originating from different regions of Hungary, 52 Actinobacillus pleuropneumoniae strains were isolated that belonged to the 1st biotype. Of them, 43 could be classified into the 2nd, 4 to the 11th, while 3 to the 1st serotype. Of the 197 lungs, demonstration of the antigen by the co-agglutination test was also attempted in 110 cases. 63 samples proved to be positive: antigenic components of a single serotype could be demonstrated in 36 cases and - simultaneously - that of two or three serotypes in 27 lungs. In Hungary, only the incidence of 1st and 2nd serotypes were confirmed up to 1988. From 1989, the presence of 3rd, 7th, 9th and 11th serotypes were also diagnosed. Up to the end of June, 1991, the serotype of 484 isolates, originated from 99 herds, were determined. Distribution of the serotypes was, as follows: 58 strains belonged to the 1st, 340 to the 2nd, 10 to the 3rd, 25 to the 7th, 23 to the 9th and 28 to the 11th serotype. Based on the result of co-agglutination test, isolation of further serotypes can also be presumed. By 1989, the sero-typification had been carried out by the agglutination test. However, this method is labour-intensive and - according to the results of subsequent investigations - fals result were also obtained in certain cases. Actually, the primer typification has been carried out by the co-agglutination test. Thus, 95 to 97% of the strains can be simply and quickly determined. In doubtful cases, immunodiffusion, indirect haemagglutination and the counter-current immuno-electrophoresis tests are used. To determine the serotype of certain strains, cross-absorption of immune sera is also required.