Decoding the diet: Determining Culicoides host associations in Arkansas

Culicoides are small hematophagous flies that transmit bluetongue virus (BTV) and epizootic hemorrhagic disease virus (EHDV) to wild and domestic ruminants. Culicoides host associations are often poorly described, and usually based on animal-baited traps studies, however this method does not consider the wide range of hosts Culicoides are feeding on. Culicoides tend to be generalist or opportunistic feeders, however some host preferences have been documented. Accurately identifying host preferences will allow for targeted vector control and surveillance. In this study, blood meal analysis was conducted on field collected engorged Culicoides through PCR amplification of extracted host DNA. 16S rRNA and cytochrome b genes were targeted using three primers sets. Samples were initially screened for mammalian and amphibian hosts, followed by avian hosts, and then reptiles. 298 engorged midges were collected across Arkansas between May-October 2021-2022 using UV-baited CDC suction traps. Species collected included, C. bigutattus, C. stellifer, C. haematopotus, C. venustus, C.hinmani, C.crepuscularis, C. guttipennis, C. variipennis, C. arboricola, and C. debilipalpis. Sample processing is currently in progress. We anticipate a range of host preferences, with putative vector species, such as C. stellifer, targeting large ruminants, and ornithophilic species, such as C. haematopotus targeting birds. The results of this study can be used to implement targeted control strategies and inform producers and researchers of hosts most at risk.