Identification and morphological differentiation of microfilariae in dog blood no Espírito Santo

Abstract

The filariasis are helminths that are common in domestic dogs but may also occur in cats, horses and some wild animals. The species involved with the parasitism bring the host to a case of microfilaremia, producing microfilariae that are very similar to each other, which makes the diagnosis difficult. This work aimed to clarify the morphologic differences between the microfilariae of the main filarial worms in dogs, specially Dirofilaria immitis e Acanthocheilonema reconditum. For the study, blood samples of dogs in Espírito Santo were collected by veterinarian laboratories previously diagnosed as positive using blood smear, and forwarded to the Parasitology Lab of the Veterinary Hospital of the Federal University of Espírito Santo. The samples were submitted to modified Knott test and analyzed on slide under optical microscope for morphometric characterization, based on its main morphological characteristics from head and tail and subsequent differentiation of the microfilaria species found. Seventy-two samples were analyzed, being 69.44% represented infection by D. immitis and 15.27% by A. reconditum, from which 12.5% were infected by both species. There was no evidence that would suggest other species of filarial worms.