Evolutionary Origins, Diversification, and Biogeography of Liver Flukes (Digenea, Fasciolidae)

Abstract

Fasciolid flukes are among the largest and best known digenetic trematodes and have considerable historical and veterinary significance. Fasciola hepatica is commonly implicated in causing disease in humans. The origins, patterns of diversification, and biogeography of fasciolids are all poorly known. We have undertaken a molecular phylogenetic study using 28S, internal transcribed spacer 1 and 2 (ITS-1 and ITS-2) of nuclear ribosomal DNA, and mitochondrial nicotinamide dehydrogenase subunit 1 (nad1) that included seven of the nine recognized species in the family. The fasciolids examined comprise a monophyletic group with the most basal species recovered from African elephants. We hypothesize fasciolids migrated from Africa to Eurasia, with secondary colonization of Africa. Fasciolids have been conservative in maintaining relatively large adult body size, but anatomical features of their digestive and reproductive systems are available. These flukes have been opportunistic, with respect to switching to new snail (planorbid to lymnaeid) and mammalian hosts and from intestinal to hepatic habitats within mammals.

Post-Mortem Evaluation of Pathological Lesions in European Bison (Bison Bonasus) in the Białowieża Primeval Forest Between 2008 and 2013

“…Environmental factors such as higher water acidity can also affect the invasiveness of F. hepatica (27), which should be considered when planning the eradication/control strategy against these parasites in bison. In addition, Demiaszkiewicz (7) identified a relative of the F. hepatica fluke, Parafasciolopsis fasciolaemorpha, (25) present in 9% of European bison. The parasite is prevalent mainly in elk in Europe, but it may be also transmitted to other cervids and domestic ruminants (7,25).…”

“…In addition, Demiaszkiewicz (7) identified a relative of the F. hepatica fluke, Parafasciolopsis fasciolaemorpha, (25) present in 9% of European bison. The parasite is prevalent mainly in elk in Europe, but it may be also transmitted to other cervids and domestic ruminants (7,25).…”

Radix spp.: Identification of trematode intermediate hosts in the Czech Republic

“…Particular species of the genus Radix may differ in their susceptibility to medically and/or veterinary important trematodes belonging to bird schistosomes (family Schistosomatidae, especially the genus Trichobilharzia Skrjabin et Zakharow, 1920) (Horák et al 1998(Horák et al , 2002Ferte et al, Horák and Kolářová 2011) and fasciolids (family Fasciolidae, especially the genus Fascioloides Ward, 1917) (Dreyfus et al 1997, Faltýnková et al 2006, Caron et al 2007, Lotfy et al 2008, Mas-Coma et al 2009). Only susceptible snails play a role in parasite transmission and have impact on epidemiological/epizootiological situation.…”

Issues Associated with Genetic Diversity Studies of the Liver Fluke, Fasciola Heptica (Platyhelminthes, Digenea, Fasciolidae)

“…Most commonly utilized variable regions are ITS 1, ITS 2 and D-domains (divergent regions in 28S and 18S genes). As it concerns F. hepatica many research teams have applied above mentioned rDNA genes in multiple investigations (Lee et al, 2007;Olson et al, 2003;Lotfy et al, 2008;Vara-Del Río et al, 2007;Marcilla et al, 2002, etc.). D1-region from 28S rDNA has been used for genetic structuring of the populations of species from phylum Platyhelmintes (Lee et al, 2007).…”

“…The results from that investigation have enabled clarifying of taxonomy, phylogeny and evolutionary relationships in the class. As it concerns the evolution and origin of fasciolid species and liver fluke in particular, Lotfy et al (2008) utilized 28S rDNA, ITS 1 and ITS 2 spacers to establish monophyleticity of that group. Using the nucleotide sequences and phylogenetic relationships of mentioned ribosomal regions the authors described evolutionary processes that occurred with fasciolid species and defined their origin.…”