Host Associations of <i>Culicoides</i> Biting Midges in Northeastern Kansas, USA.

Abstract

<i>Culicoides</i> biting midges (Diptera: Ceratopogonidae) are hematophagous flies that transmit several viruses of veterinary concern to livestock. Understanding blood feeding behaviors is integral towards identification of putative vector species and preventing the transmission of these pathogens. PCR-based blood meal analysis was conducted on 440 blood-engorged <i>Culicoides</i> midges collected in northeastern Kansas, with 316 (71.8%) returning non-human vertebrate identifications at the ≥95% identity match level. Broadly, <i>Culicoides sonorensis</i>, <i>Culicoides stellifer</i>, and <i>Culicoides variipennis</i> were found to feed heavily on mammalian hosts, while <i>Culicoides crepuscularis</i> and <i>Culicoides haematopotus</i> fed on avian hosts. The blood meals in all specimens were graded prior to DNA extraction to determine whether blood meal size or digestion status significantly impacted the likelihood of a quality host match. Size had a significant impact on the likelihood of a quality match at grades 3-5, whereas digestion only significantly impacted outcomes at the most extreme grade. These vector-host dynamics have not previously been studied in <i>Culicoides</i> collected in Kansas, which represents a unique tallgrass prairie biome within the United States that is heavily interspersed with livestock operations. Based on these data, the highly abundant species <i>C. crepuscularis</i> and <i>C. haematopotus</i> are unlikely to be major vectors of mammalian viruses.