Towards understanding the liver fluke transmission dynamics on farms: Detection of liver fluke transmitting snail and liver fluke-specific environmental DNA in water samples from an irrigated dairy farm in Southeast Australia

Environmental detection of Fasciola hepatica by loop-mediated isothermal amplification

“…Here we present a simple method of concentrating DNA from environmental water samples suitable for use in FhLAMP, amplifying as little as 1 × 10 −3 ng/µL F. hepatica gDNA back calculated from 250 mL spiked moat water, partially filtered. Though the sensitivity in this study is ten-fold less than the results obtained by qPCR in Rathinasamy et al (2021) , reported as 1 × 10 −4 ng/µL, filtering greatly reduced processing time to less than 15 min for five water samples irrespective of starting volume (50 or 250 mL), down from at least 1 h for spin-column or eDNA clean-up methods ( Czeglédi et al, 2021 ; Rathinasamy et al, 2021 ). Despite high levels of non-target DNA and DNA polymerase inhibitors present in freshwater samples, amplification of filtered water samples using FhLAMP maintained high specificity, correctly amplifying all samples containing F. hepatica gDNA despite the presence of large invertebrate species known to inhabit freshwater, including freshwater shrimp, mosquito larvae, midges, and nymphs ( Gooderham & Tsyrlin, 2002 ; McNally et al, 2013 ).…”

“…Despite high levels of non-target DNA and DNA polymerase inhibitors present in freshwater samples, amplification of filtered water samples using FhLAMP maintained high specificity, correctly amplifying all samples containing F. hepatica gDNA despite the presence of large invertebrate species known to inhabit freshwater, including freshwater shrimp, mosquito larvae, midges, and nymphs ( Gooderham & Tsyrlin, 2002 ; McNally et al, 2013 ). Additionally, mean F. hepatica eDNA quantity detected over seven sampling periods in Rathinasamy et al (2021) was 2.4 × 10 −3 ng/µL (2IQR: 9.9 × 10 −4 ng/µL). This suggests that the extraction-free method reported here is sufficient for F. hepatica eDNA sampling, despite partial volumes of ~100 mL of 250 mL spiked samples filtered, with FhLAMP detecting 1 × 10 −3 ng/µL using this crude concentration method.…”

Environmental DNA in human and veterinary parasitology - Current applications and future prospects for monitoring and control

“…– 4 species Freshwater qPCR ( Rudko et al, 2019 ) Snail-host Oncomelania hupensis quadrasi Soil qPCR ( Calata et al, 2019 ) Vector Culicidae Freshwater qPCR / Metabarcoding ( Krol et al, 2019 ) Vector Culicidae Freshwater and sediment Metabarcoding ( Boerlijst et al, 2019 ) Parasite + Snail-host Schistosoma japonicum Oncomelania hupensis quadrasi Freshwater qPCR ( Fornillos et al, 2019 ) Snail-host Bulinus truncates Freshwater qPCR / ddPCR ( Mulero et al, 2019 ) Parasite Schistosoma mansoni Schsitosma haematobium Schistoma japonicum Freshwater qPCR ( Alzaylaee et al, 2020a ) Parasite Schistosoma mansoni Schsitosma haematobium Freshwater qPCR ( Alzaylaee et al, 2020b ) Parasite Schistoma haematobium Freshwater qPCR ( Eyre et al, 2020 ) Parasite Trichobilharzia sp. Freshwater qPCR ( Rudko et al, 2020 ) Snail-host Galba truncatula Freshwater LAMP ( Davis et al, 2020 ) Parasite + Snail-host Fascila + Austropeplea tomentosa Freshwater Multiplex qPCR ( Rathinasamy et al, 2021 ) ...…”

Current Status for Controlling the Overlooked Caprine Fasciolosis

“…There are practical farming practices that can be immediately implemented to prolong the activity of commercial drugs and control fluke infections in goats. Recently, the development of molecular tests for identifying environmental DNA (eDNA) from F. hepatica or intermediate host snails ( A. tomentosa and G. truncatula ) can allow the accurate determination of fluke-contaminated areas on farms [ 172 , 173 , 174 ]. Monitoring eDNA shed from free-living life stages of flukes or transmitting snails would allow for precise identification of transmitting zones and snail habitats for sound advice on the use of molluscicides and fencing off regions on farms.…”