Diversity, Abundance and Host Blood Meal Analysis of Culicoides Latreille (Diptera: Ceratopogonidae) from Cattle Pens in Different Land Use Types from Thailand

Simple Summary Biting midges are small blood-sucking insects that are pests and vectors of several pathogens transmitted to humans and other animals. Understanding the factors that are associated with species diversity, distribution, and abundance, as well as host preference, is crucial for the control and management of these insects. In this study, we examined species diversity, abundance, and identification of the host blood source of the biting midge genus Culicoides Latreille collected from cattle pens located in three different land use areas. We found that cattle pens located in villages and agricultural lands had greater abundance but were less diverse than those located close to the forest. The identification of the host blood source revealed that biting midge species in the cattle pens preferred buffalos rather than cows or chickens, although the latter two were much more abundant. Information gathered from this study will be useful for monitoring and understanding vectorial capacity as well as disease epidemiology involving the biting midge species found in cattle pens. Biting midges of the genus Culicoides Latreille are significant pests and vectors that transmit pathogens to humans and other animals. Cattle are among the important livestock that can potentially be severely affected by Culicoides. In this study, we examined the species diversity, abundance, and host blood meal identification of biting midges in cattle pens located in three different land use types: villages, agricultural areas, and the forest edge. A total of 12,916 biting midges were collected, and most of these were from cattle pens located in villages (34%) and agricultural land (52%). Morphological identification revealed 29 Culicoides species. The most common species were C. oxystoma, C. mahasarakhamense, C. peregrinus, and C. shortti; taken together, these species represented >80% of all specimens collected. Despite midges being less numerous (14% of the total collection), cattle pens located near the forest showed greater diversity (23) than those from villages and agricultural areas. More diverse immature habitats and host blood sources from wildlife in nearby forests possibly explain the greater diversity in the cattle pens near the forest edge. Host blood meal analysis revealed that most (65%) biting midges had fed on buffalo despite the fact that this animal was much less numerous than cows or chickens. Relatively larger size and black-colored skin could be factors that make buffalo more attractive to biting midges than other host species. In this study, we also provided 67 DNA barcoding sequences of 13 species, three of which (C. flaviscutatus, C. geminus, and C. suzukii) were first reported from Thai specimens. DNA barcode analysis indicated cryptic diversity within C. hegneri and C. flavescens in Thailand, and thus, further investigation is required to resolve their species status.

Automated summary

In this study, we investigated the species diversity, abundance, and host blood source of the biting midge genus Culicoides Latreille in cattle pens located in three different land use areas. We found that cattle pens in villages and agricultural lands had higher abundance but lower diversity compared to those near the forest. Biting midge species in the cattle pens preferred buffalos as their blood source, despite their lower abundance compared to cows or chickens.