Figure 2
A cross-sectional serological screening for mean serum antibody levels (A 450 ) to Actinobacillus pleuropneumoniae serotype 2 performed during an outbreak of actinobacillosis in a specialized fattening herd employing age segregated rearing. Six pigs per unit were analysed. The error bars show positive standard deviations and the dotted line indicates the cut-off value for a positive reaction.