Attractiveness of domestic animal shelters to Culicoides biting midges (Diptera: Ceratopogonidae) in the Eastern Amazon

Biting midges of the genus Culicoides (Diptera: Ceratopogonidae) are known for their medical and veterinary importance. The presence of these insects in domestic animal shelters can pose significant risks to animal and public health. This study aimed to assess the richness, abundance, and seasonal frequency of Culicoides biting midges in domestic animal shelters located in the backyards of human residences. Insects were collected once a month from August 2016 to July 2018 in pigsties, chicken coops, corrals, sheep pens, and goat pens in three rural villages in Vitória do Mearim, Maranhão State, Brazil. The data were subjected to one-way analysis of variance and Tukey's post hoc test to verify differences in infestation between shelters and determine which shelter types were most attractive to midges. A total of 2801 individuals belonging to 13 species of Culicoides were captured. Richness was highest in pigsties (11 species) and chicken coops (10), whereas abundance was highest in chicken coops (45.6%), cattle corrals (27.7%), and pigsties (19.7%). Biting midges occurred throughout the year but prevailed in the rainy season (13 species, 64.4% of individuals), when humidity is high and temperatures and winds are milder. Backyard infestations demonstrate the important role of domestic animals and their shelters in attracting biting midges. This study recommends implementing backyard cleaning efforts focused on animal shelters as part of an environmental management strategy to prevent midge infestations. Additionally, conservation actions should be undertaken in adjacent forest areas to preserve the environmental conditions that support these insects in their natural habitats.