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Francis, E. K.

Publications and source records attributed to Francis, E. K..

2 recordsLinked to original sources

Ambient temperature storage in DESS supports molecular studies of benzimidazole resistance from canine hookworm eggs

Emerging benzimidazole resistance in canine hookworms poses a growing concern for veterinary and public health. Molecular diagnostics targeting {beta}-tubulin gene mutations are essential for resistance surveillance but traditionally rely on refrigerated faecal samples. This study evaluates dimethyl sulfoxide, EDTA, and saturated NaCl (DESS) as a room-temperature preservation medium for canine faeces. Using ITS-2 rDNA and isotype-1 {beta}-tubulin gene (tubb-1) amplicon metabarcoding, we compared DNA integrity and diagnostic performance of DESS-preserved samples (4, 28, and 106 days) to refrigerated controls. No significant differences in PCR amplification or sequencing outcomes were observed. DESS enabled reliable detection of hookworm species and resistance-associated SNPs, including F167Y in tubb-1, with mutation frequencies consistent across treatments. Therefore, DESS can preserve samples from remote settings without cold chain logistics. Our findings validate DESS as a robust alternative for sample collection for molecular parasitology, facilitating expanded surveillance of anthelmintic resistance in field conditions. HighlightsO_LIDESS preserves canine faeces for DNA analysis without refrigeration. C_LIO_LIHookworm species and resistance SNPs detected reliably from DESS samples. C_LIO_LIPCR and NGS results from DESS samples match refrigerated controls. C_LIO_LIF167Y mutation found in A. caninum and U. stenocephala samples. C_LIO_LIDESS enables remote hookworm surveillance without cold chain logistics. C_LI

microbiology↗

A mixed amplicon metabarcoding and sequencing approach for surveillance of drug resistance to levamisole and benzimidazole in Haemonchus spp.

Anthelmintic resistant parasitic nematodes present a significant threat to sustainable livestock production worldwide. The ability to detect the emergence of anthelmintic resistance at an early stage, and therefore determine which drugs remain most effective, is crucial for minimising production losses. Despite many years of research into the molecular basis of anthelmintic resistance, no molecular-based tools are commercially available for the diagnosis of resistance as it emerges in field settings. We described a mixed deep amplicon sequencing approach to determine the frequency of the levamisole (LEV) resistant single nucleotide polymorphism (SNP) within arc-8 exon 4 (S168T) in Haemonchus spp., coupled with benzimidazole (BZ) resistance SNPs within {beta}-tubulin isotype-1 and ITS-2 nemabiome. This constitutes the first multi-drug and multi-species molecular diagnostic developed for helminths of veterinary importance. Of the ovine, bovine, caprine and camelid Australian field isolates we tested, S168T was detected in the majority of Haemonchus spp. populations from sheep and goats, but rarely at a frequency greater than 16%; an arbitrary threshold we set based on whole genome sequencing of LEV resistant H. contortus GWBII. Overall, BZ resistance was far more prevalent in Haemonchus spp. than LEV resistance, confirming that LEV is still an important anthelmintic class for small ruminants in New South Wales. The mixed amplicon metabarcoding approach described herein, paves the way towards the use of large scale sequencing as a surveillance technology in the field, the results of which can be translated into evidence-based recommendations for the livestock sector.

microbiology↗