Studies on the possibility of rearing seronegative animals within a breeding and rearing herd infected with Actinobacillus pleuropneumoniae serotype 2.

In two sanitation trials it was not possible to rear seronegative animals within a breeding and rearing herd heavily infected with Actinobacillus pleuropneumoniae serotype 2. Neither medication with sulphonamides-trimethoprim of the sows and piglets or the sows alone nor a strictly applied all-in all-out system reduced the percentage of seropositive animals.