Table 1.

Measures (μm) of microfilariae determined after fixation with the modified Knott’s technique

Microfilariae species identified by histochemical staining and partially confirmed by PCRa	Total number and origin of dogs	Mean length ± standard deviation (μm)	Mean width ± standard deviation (μm)
Dirofilaria immitis	60 (GR 1; IT 6; PT 33; ES 16; TR 2; UO 2)	301.77 ± 6.29	6.30 ± 0.26
Dirofilaria repens	171 (BG 1; FR 1; GR 5; IT 10; RO 3; ES 2; HU 141; UO 8)	369.44 ± 10.76	8.87 ± 0.58
Acanthocheilonema dracunculoides	133 (PT 69; ES 55; UO 9)	259.43 ± 6.69	5.09 ± 0.47
Acanthocheilonema reconditum	13 (IT 13)	264.83 ± 5.47	4.63 ± 0.52

Mean length and mean width (μm) of microfilariae determined after fixation with the modified Knott’s technique of confirmed single filarial infections in 377 dogs.

IT, Italy; ES, Spain; GR, Greece; PT, Portugal; RO, Romania; HU, Hungary; BG, Bulgaria; TR, Turkey; FR, France; Unknown Origin: UO.

^a PCR confirmation for 6 samples positive for D. immitis, 4 for D. repens, 7 for A. dracunculoides and 6 for A. reconditum infections.