No abstract

No abstract

No abstract

Summary To determine the prevalence of A. pleuropneumoniae serotypes in Finnish pig populations, 692 blood samples of sows were randomly collected from Finnish slaughterhouses. These were assayed with a direct ELISA for 12 Actinobacillus pleuropneumoniae serotypes. The specificity of the ELISA was tested using rabbit antisera against these serotypes. Cross‐reactions were detected between serotypes 6 and 8 and between serotypes 1, 9 and 11, and serotype 5 antiserum reacted with serotype 6 antigen, but the other serotypes did not cross‐react. When assaying the blood samples serotype 3 and 2 antibodies were found in 51 % and 26 % of samples, respectively. Other serotypes were found only in smaller numbers. Most of the samples, 61 %, had antibodies towards some serotype of A. pleuropneumoniae. Antibodies towards serotypes 2 and 3 were found in pigs throughout Finland.

A direct ELISA with phenol-extracted antigen for Actinobacilluspleuropneumoniae serotype 2 was developed. The test was specific when tested with rabbit antisera prepared against different A. pleuropneumoniae serotypes. It had better-than-moderate repeatability and it made a clear distinction between positive and negative samples.A total of 5477 colostrum samples from breeding sows from herds participating in the Finnish Pig-health Scheme were tested using the ELISA test. A total of 1307 positive samples were found in 129 out of 154 herds, thus indicating that most of the disease-control herds in Finland are infected with A. pleuropneumoniae serotype 2. These infections were almost entirely subclinical.::. Corresponding author U.S.