Trypanosomatids in Bloodsucking Diptera Insects (Ceratopogonidae and Simuliidae) Wild-Caught at Raptor Bird Nests in Temperate Forests

Abstract

Trypanosomatids are a huge group of vertebrate, invertebrate and plant parasites that can cause severe illnesses in hosts. Although avian trypanosomes are widely spread throughout the world, information about their transmission and vector–host relationships is still scarce. This study aimed to investigate Trypanosoma prevalence in bloodsucking Diptera collected at tree-nesting raptor birds’ nests. Insects were collected in temperate forests of Eastern-Central Europe, in Lithuania, using UV light traps hung near common buzzard (Buteo buteo) and lesser spotted eagle (Clanga pomarina) nests at about 15 m height above the ground. A total of 1248 Culicoides (Ceratopogonidae) females and 3 blackflies (Simuliidae) were collected and tested for the presence of trypanosomatids using PCR-based methods. The blood of 85 nestlings, belonging to three different species (Buteo buteo, Clanga pomarina and Haliaeetus albicilla) was collected and tested using the same methods. We found that 11.1% of the investigated insects (one Simulium female and Culicoides biting midges belonging to five species) were infected with Trypanosoma parasites (Trypanosoma sp., T. bennetti group, T. avium) and monoxenous trypanosomatids (Crithidia sp., Obscuromonas sp.). Only one common buzzard nestling was found to be infected with Trypanosoma avium. The phylogenetic relationships of detected parasites were determined. Our findings supplement information on the ornithophilic behavior of Culicoides females, potential vector species of avian Trypanosoma, and produce some new information on the detection of monoxenous trypanosomatids (Crithidia sp. and Obscuromonas sp.) in Culicoides.