Flystrike, caused predominantly by the Australian sheep blowfly (Lucilia cuprina), remains one of the most significant animal welfare and production challenges facing the sheep industry, costing the Australian wool sector an estimated AUD$356 million annually. Increasing resistance to conventional insecticides has reduced the effectiveness of existing control measures and highlighted the need for novel, sustainable approaches. RNA interference (RNAi) offers a species-specific and environmentally compatible strategy for pest control; however, practical implementation has been constrained by two major barriers: identification of effective molecular targets and delivery of double-stranded RNA (dsRNA) in a form that remains stable and biologically active under field-relevant conditions.
To address these challenges, we developed an integrated RNAi pipeline spanning target discovery through to delivery. We established a novel L. cuprina cell line and utilized it as a high-throughput screening platform to identify genes essential for blowfly survival and development. Candidate double-stranded RNA (dsRNA) targets identified through cell-based screening were subsequently validated in larval bioassays. This approach generated a shortlist of RNAi targets with demonstrated efficacy and specificity.
To overcome limitations associated with dsRNA delivery, we developed BenPol, a bentonite-polymer carrier system designed to improve dsRNA stability and uptake. BenPol formulations protected dsRNA from degradation, enhanced cellular uptake and facilitated sustained target gene knockdown in feeding assays. Compared with unformulated dsRNA, BenPol-mediated delivery improved gene silencing during larval exposure. Building on these findings, ongoing studies are focusing on evaluating formulation performance under increasingly realistic delivery scenarios to support translation towards animal-relevant applications.
Collectively, this work establishes an end-to-end RNAi development framework for L. cuprina, integrating target identification, validation, biosafety assessment and advanced dsRNA delivery within a single platform. By addressing critical barriers this research advances the development of next-generation flystrike control technologies and provides a foundation for broader application of RNAi-based pest management strategies in agricultural and veterinary systems.