Comparison of previous mPCR (8), and new APP mPCR1 for detection of A. pleuropneumoniae serovars 2, 8, and K2:O7. The K2:O7 isolates (7317/84 in lane 1; 9712534 in lane 2) produced amplicons indicative of both serovars 2 and 8 with the previous mPCR (A), but only the correct serovar 2 amplicon with APP mPCR1 (B). Lanes 3 and 4 contain serovar 2 strain S1536 and serovar 8 strain 405, respectively. Lane M contains molecular size markers (100-bp Plus DNA Ladder; Invitogen).