Some potential mosquito vectors of the canine heartworm, Dirofilaria immitis, in the Calgary region of southern Alberta

Abstract

A total of 657 mosquitoes, representing eight species from the Calgary region of southern Alberta was fed on dogs infected with Dirofilaria immitis. Complete development to the infective stage occurred in Aedes campestris, A. cataphylla, A. flavescens, and A. vexans. The rate of development appeared dependent on the temperature, as well as on the vector species. This report is believed to be the first account on the development of D. immitis in the first three species. Third stage larvae recovered from A. flavescens and A. vexans, inoculated subcutaneously into either two dogs or two white laboratory rats, produced microfilaremias in both dogs and a single adult, male D. immitis in the thoracic cavity of one of the rats. It is suggested that these species may act as vectors under natural conditions and that the identification of the potential vectors of D. immitis in areas where it is currently not endemic is important since this knowledge can be used in the planning of prophylactic measures.