Author ORCID Identifier:
Date of Graduation
5-2026
Document Type
Dissertation
Degree Name
Doctor of Philosophy in Agricultural, Food and Life Sciences (PhD)
Degree Level
Graduate
Department
Agricultural, Food and Life Sciences
Advisor/Mentor
McDermott, Emily
Committee Member
Goggin, Fiona
Second Committee Member
Powell, Jeremy
Third Committee Member
Loftin, Kelly
Keywords
blue tongue virus; culicoides biting midges; fluralaner; isoxazoline; vector competence
Abstract
The most recently introduced class of chemical insecticides in the United States (US) are the isoxazolines, including fluralaner. In the US, fluralaner is exclusively labeled for use against ectoparasites in companion animals and poultry, however, research has shown that it has a substantially wider range of efficacy. To add to the growing body of literature demonstrating fluralaner’s potential, this dissertation explores the use of this synthetic insecticide to control Culicoides biting midges (Diptera: Ceratopogonidae). Biting midges are blood-feeding pathogen vectors closely associated with livestock production. Yet compared to their mosquito counterparts, Culicoides are understudied and management tools are lacking. In anticipation of adding another class of chemicals into rotation to vector control programs, fluralaner’s efficacy against Culicoides was explored as an adulticide and larvicide. Consistent with similar studies, I show that the most potent route of exposure at both life stages is orally, as it allows fluralaner to bypass the cuticular barrier. The fluralaner larvicide formulation presented in this dissertation shows to be a promising candidate as a product targeting natural detritovorous larvae. Furthermore, the downstream effects of sublethal exposure to pesticides were evaluated. Exposure to chemical pesticides at sublethal levels as larvae leads to developmental trade-offs that can lead to lasting physiological changes, including vector competence for pathogens as adults. Larvicide exposure can directly impact larval survival but also influence gene expression patterns that govern development and long-term fitness. This overlap reflects the integration of detoxification in immunity as a response to both chemical stress and pathogenic threats. As a result, detoxifying pesticides at sublethal levels may developmentally compromise insect vectors, making them more vulnerable to infections. In this study, a holistic and comprehensive investigation into fluralaner’s efficacy against Culicoides sonorensis is presented and resultant changes in vector competence are discussed.
Citation
Bunkers, B. (2026). Exploring the Potential of Fluralaner in Vector Control for Culicoides Biting Midges. Graduate Theses and Dissertations Retrieved from https://scholarworks.uark.edu/etd/6209
