title: Evaluation of molecular methods for the field study of the natural history of Dicrocoelium dendriticum.
abstract: There is a need for improved methods for the study of the impacts of climatic and livestock management change on the epidemiology of production-limiting helminth parasitic diseases. In this study we report the application of molecular methods to describe the natural history of the small lancet fluke, Dicrocoelium dendriticum on Machair pastures on the Inner Hebridean Isle of Coll. Our results build upon those of the only previous historic field study of D. dendriticum in the British Isles that had been undertaken on the same study site. We demonstrate the value of combining conventional parasitological methods with PCR amplification of a mitochondrial DNA fragment for the detection of D. dendriticum in ants and snails, and PCR amplification of ITS2 and 28S ribosomal DNA fragments to support the species identity of the intermediate hosts, to improving understanding of the epidemiology of D. dendriticum. We report the presence of D. dendriticum infection in cattle, sheep and rabbits grazing on Machair pastures. D. dendriticum infection was identified in a high percentage of the snails, identified as Cochlicella acuta and Cernuella virgata, and in a high percentage of Formica fusca and Myrmica ruginoides ants that were collected from, or clinging to, the tops of flowers. We have identified the involvement of different intermediate host species and higher prevalences of snail and ant infection than previously reported, in part reflecting differences between the sensitivity and specificity of morphological and molecular speciation methods. Overall, our results highlight the complex life history of dicrocoeliosis and illustrate the parasite's generalist host strategy that confers potential to exploit new niches created by climatic change or grazing management for habitat conservation.
authors.affiliation: Moredun Research Institute, Pentlands Science Park, Edinburgh EH26 0PZ, United Kingdom.
authors.forename: Gillian
authors.initials: G
authors.lastname: Mitchell
authors.affiliation: Moredun Research Institute, Pentlands Science Park, Edinburgh EH26 0PZ, United Kingdom.
authors.forename: Grace
authors.initials: G
authors.lastname: Cuthill
authors.affiliation: University of Edinburgh, Royal (Dick) School of Veterinary Studies and Roslin Institute, Easter Bush Veterinary Centre, Roslin, Midlothian EH25 9RG, United Kingdom.
authors.forename: Alex
authors.initials: A
authors.lastname: Haine
authors.affiliation: Moredun Research Institute, Pentlands Science Park, Edinburgh EH26 0PZ, United Kingdom.
authors.forename: Ruth
authors.initials: R
authors.lastname: Zadoks
authors.affiliation: University of Edinburgh, Royal (Dick) School of Veterinary Studies and Roslin Institute, Easter Bush Veterinary Centre, Roslin, Midlothian EH25 9RG, United Kingdom.
authors.forename: Umer
authors.initials: U
authors.lastname: Chaudhry
authors.affiliation: Moredun Research Institute, Pentlands Science Park, Edinburgh EH26 0PZ, United Kingdom.
authors.forename: Philip
authors.initials: P
authors.lastname: Skuce
authors.affiliation: University of Edinburgh, Royal (Dick) School of Veterinary Studies and Roslin Institute, Easter Bush Veterinary Centre, Roslin, Midlothian EH25 9RG, United Kingdom. Electronic address: neil.sargison@ed.ac.uk.
authors.forename: Neil
authors.initials: N
authors.lastname: Sargison
mesh_terms: D000818:Animals; D001000:Ants / Q000469:parasitology*; D002417:Cattle; D018509:DNA, Helminth / Q000737:chemistry / Q000235:genetics; D004272:DNA, Mitochondrial / Q000737:chemistry / Q000235:genetics; D021903:DNA, Ribosomal Spacer / Q000737:chemistry / Q000235:genetics; D004011:Dicrocoeliasis / Q000469:parasitology / Q000662:veterinary*; D004013:Dicrocoelium / Q000235:genetics / Q000302:isolation & purification*; D004197:Disease Reservoirs / Q000662:veterinary; D005243:Feces / Q000469:parasitology; D006363:Hebrides; D016133:Polymerase Chain Reaction / Q000662:veterinary; D011817:Rabbits; D012680:Sensitivity and Specificity; D017422:Sequence Analysis, DNA / Q000662:veterinary; D012756:Sheep; D012908:Snails / Q000469:parasitology*
chemical_list: D018509:DNA, Helminth; D004272:DNA, Mitochondrial; D021903:DNA, Ribosomal Spacer
keywords: Ant; Dicrocoelium dendriticum; Machair; Molecular methods; Snail