Detrimental effects of Haemoproteus infections on the survival of biting midge Culicoides impunctatus (Diptera: Ceratopogonidae).

Abstract

The effects of Haemoproteus belopolskyi, Haemoproteus fringillae, and Haemoproteus lanii on the survival of their vector the biting midge Culicoides impunctatus were examined. Wild-caught females were infected experimentally by allowing them to feed on naturally infected birds. A group of flies, which fed on an uninfected bird, was used as a control. There was a highly significant difference in the survival rate between the noninfected group and all groups of infected flies for postfeeding (PF) periods 1-2, 3-4, 5-6, and 7-8 days. For days 7-8, the percentage of noninfected surviving flies was 4.4 times higher than the percentage of infected surviving flies, testifying to the detrimental effects of avian Haemoproteus infections on the longevity of C. impunctatus. The mortality rates of the infected flies were highest for days 1-2 and 3-4 PF, indicating possible negative effects of ookinetes and early oocysts on the vector.