Figure 3.

Multiplex polymerase chain reaction amplification of DNA after agarose gel separation. Lanes 1 and 2: sample, tested in duplicate; lane +im: positive Dirofilaria immitis control; lane +re: positive Dirofilaria repens control; lane neg: negative control; (*) non-specific amplification products. The ~500-base pair (bp) fragment observed in both the tested samples and positive controls is the result of the amplification of a 12s rDNA region highly conserved among the nematode species. The 204-bp D immitis-specific fragment is only visible in lanes 1, 2 and +im. The 327-bp D repens-specific fragment is only found in the +re lane