Ocorrência de miíases em animais de companhia no Distrito Federal, Brasil

Ano: 2011 | Volume: 39 | Número: 3

Autores: Edison Rogerio Cansi, Caroline Demo

Palavras-chave: cochliomyia hominivorax, lucilia eximia, musca domestica, ectoparasitismo, caninos, felinos, miíase neotropical

Resumo Inglês:

Background: Myiasis is one of the main causes of infestation by Diptera larvae in animals and human beings. This parasitic
disease is frequently diagnosed at veterinary and medical practices. It is classified according to its anatomical location in the
host or to its dependency relations and parasitic occurrence. In Brazil, the two diptera species with the highest myiasis
incidence in domestic animals are Cochliomyia hominivorax (Calliphoridae) and Dermatobia hominis (Oestridae). These
ectoparasites are primarily found in dogs and secondarily in cats, and they are often associated with omission or mistreatment
by the owner. This study describes myiasis cases and the main predisposing factors in domestic animals that occurred in 2009
in the Federal District, Brazil.
Materials, Methods & Results: Between January and December 2009, veterinary practitioners from 90 small animal practices
were requested to supply the larvae collected from clinical myiasis cases. The larvae were kept alive inside biological
containers containing vermiculite to preserve their integrity during transportation. Data on the collection month, age, gender,
breed, color and type of coat, as well as lesion site, myiasis type and dwelling type were obtained. The larvae were identified
in laboratory and then kept inside incubators, fed on rotten bovine meat during 24h. The resulting flies were again identified
and sexed. Then the absolute and relative proportions of the clinical cases were obtained, based on the epidemiological factors
and respective parasites. Forty cases were recorded (39 of which were dogs and one was a cat). Cochliomyia hominivorax was
the most abundant parasite, with 37 cases observed in dogs and only one in a cat. The other two myiasis cases were caused by
Lucilia eximia and Musca domestica. In dogs, the highest occurrence of myiasis was observed in males, especially in German
Sheepdogs and Cocker Spaniels. The predominant anatomical sites of the disease in dogs were the front limbs and tail. The
period in which the disease occurred most frequently was between March and May, period which corresponds to the rainy
season in the Brazilian Cerrado. Dogs living in houses within urban areas had the highest parasitism occurrence.
Discussion: Myiasis in companion animals is a common finding throughout practices in Brazil and around the world. However,
this situation has been under control in North American countries, especially after erradication of myiases caused by C.
hominivorax in bovines, which represented great economic losses. Therefore, the incidence of the parasitism in dogs and cats
was reduced. In Brazil, obligatory and facultative cutaneous myiases in dogs and cats are caused by omission and mistreatment
by the owner. The results presented in this study corroborate the characteristics of neotropical myiases in the Southeast and
South region of Brazil in relation to the incidence period and preferential host characteristics, except that the disease has a
preference for male light-colored animals, being predominantly observed on the hind limbs. New cases were observed in dogs,
particularly in Central Brazil, such as the facultative cutaneous myiasis cases caused by Lucilia eximia and Musca domestica.