Registro de miíase por Cuterebra apicalis em cão doméstico na região Central do Brasil

Ano: 2011 | Volume: 39 | Número: 2

Autores: Edison Rogerio Cansi

Palavras-chave: miíase, cuterebra apicalis, diptera, cuterebrose, cão, região neotropical, cerrado

Resumo Inglês:

Background: Cuterebrosis is a furuncular myiasis caused by a dipterous from the genus Cuterebra. These flies are highly
species-specific in relation to their hosts, being mostly common to rodents, lagomorphs and marsupials, with the development
of a large subcutaneous furuncle as the main clinical manifestation. The most important microscopic alterations are the
invasion of the damaged area by neutrophils, lymphocytes, macrophages, eosinophils and mast cells and the proliferation of
fibroblasts and endothelial cells. However, the Cuterebrosis can occur in domestic animals, causing the formation of an
atypical parasitic cycle, with the development of significant and severe clinical signs due to the erroneous migration of larvae,
a situation not observed in typical hosts. Neuritis has been verified in cats due to the migration triggered by the larvae, causing
irreversible damage to the central nervous system. In Brazil no reports of cases of myiasis in dogs and cats have been reported
for any species of Neotropical Cuterebra. One of the species most commonly found in studies parasitizing mammals in the
Midwest is Cuterebra apicalis. However, this Diptera has only been found parasitizing marsupials Didelphidae rodents and
rodent Cricetidae. This study notifies the first case of furuncular obligatory myiasis in a dog in Central Brazil, in the Federal
District, caused by Cuterebra apicalis.
Case: In November 2009, an adult female Poodle dog (eight years old), was received from an urban area of the Federal District
(Vicente Pires), an area close to large remnants of Cerrado stricto sensu. The dog was treated at a private veterinary clinic in
Brasilia. The animal presented a furuncular myiasis in the lumbar region. Larvae were detected at the lesion site, which was
collected for clinical veterinary analysis and sent for identification, on a 20 mL container with a third of its volume filled with
vermiculite to safeguard the integrity of the material. The parasite was kept in an incubator at 25 ± 0.5°C and relative humidity
of 60 ± 0.6%. After two days, the pupae formation process initiated. Following 30 days of pupation, an adult female fly was
obtained, which was identified as from Cuterebra apicalis species.
Discussion: Although of an atypical cycle in the dog, the period of pupation and the lesions were similar to the occurrences
seen in rodents and marsupials, typical hosts of parasitism by C. apicalis in the Cerrado. Development in typical hosts occurs
on an average of 30 days, similar to the pupation in the dog case. The period of emergence of the lesion corresponded to the
rainy season in Cerrado, coinciding with an increased prevalence of infestation by the parasites in wild regional rodents,
justifying the month of occurrence. The cuterebrosis in the Nearctic region rarely completes the cycle in dogs and cats, with
parasites succumbing in the second larval stage. This is the first time larvae was observed in the final stages of development in
dogs, demonstrating that the cycle of parasitism by C. apicalis can be completed in atypical hosts. However, this study was
unable to verify the longevity and the complete cycle of the fly. This case draws attention to the degradation of the Cerrado,
with the invasion of wild species in urban areas and thus representing a potential problem for regional public health and to
domestic animals.