Molecular evidence shows that the liver fluke Fasciola gigantica is the predominant Fasciola species in ruminants from Pakistan

Abstract

Fascioliasis is an important disease affecting livestock, with great costs to producers worldwide. It has also become a serious issue for human populations in some endemic areas as an emerging zoonotic infection. There are two Fasciola species of liver fluke responsible for this disease, which occur worldwide, Fasciola hepatica and Fasciola gigantica. Identifying these two species on the basis of adult or egg morphology requires specialist knowledge due to the similarity of characters, and may misidentify putative intermediate or hybrid forms. In this study we sequenced the internal transcribed spacer 2 (ITS-2) rDNA of liver flukes collected from multiple species of hosts from seven localities in the Punjab and Baluchistan provinces of Pakistan, to determine the distribution of these two species. All 46 flukes processed in this study, collected from seven sites, showed the rDNA ITS-2 genotype corresponding to F. gigantica, contradicting previous reports, based on adult and egg morphology, that both species are present in Pakistan, with F. hepatica being the more common.

Genetic diversity and multiplicity of infection in Fasciola gigantica isolates of Pakistani livestock

“…In the present study of the dynamics of Fasciola spp. in Pakistan, ITS-2 rDNA sequence data confirmed the presence of F. hepatica, F. gigantica, and intermediate forms, with F. gigantica being the predominant species (Table 1), concurring with a previous study (Chaudhry et al, 2016).…”

Morphological and molecular identification of Explanatum explanatum in domestic water buffalo in Pakistan

“…Fasciola hepatica is generally described as occurring in temperate regions (Farjallah S, 2013;Ichikawa and Itagaki, 2010) and Fasciola gigantica in tropical areas (Amor et al, 2011), but both species overlap in subtropical areas along with intermediate genotypes (Agatsuma T, 2000). F. gigantica is the predominant species in buffalo and cattle in the Punjab and Baluchistan provinces of Pakistan (Chaudhry et al, 2015), but co-infections with F. hepatica and F. gigantica and intermediate genotypes have been described in the same region (Agatsuma T, 2000;Huang et al, 2004;Ichikawa and Itagaki, 2010;Marcilla A, 2002;Rokni MB, 2010). Dicrocoeliidae family flukes in…”

“…and 7 adult flukes were collected from with two populations obtained from Faisalabad (E1B and E10B) and one population obtained from Okara (E8B) respectively. To describe the morphology of adult liver flukes, parasites confirmed using molecular methods, as being F. gigantica were derived from different regions in Pakistan (Chaudhry et al, 2015), D. dendriticum were derived from cattle and elk in the Cypress Hills, Alberta, Canada (Beck et al, 2014).…”

A high throughput deep amplicon sequencing method to show the emergence and spread ofCalicophoron daubneyiin United Kingdom cattle herds

“…The tissue sections were then lysed in lysis buffer and Protinease K (10mg/ml, New England BioLabs). The lysis buffer contained 50 mM KCL, 10 mM Tris (pH 8.3), 2.5 mM MgCl 2 , 0.045% Nonidet p-40, 0.45% Tween-20, 0.01% gelatin and ddH 2 O in 50ml volumes (Chaudhry et al, 2015a). Samples were lysed in 50 μl for 98 minutes at 60°C followed by 15 minutes at 94°C then stored at -80°C until PCR.…”

“…Deep amplicon sequencing was performed from a 282 bp fragment of ITS-2 rDNA using previously published universal trematode primer sets (Adlard et al, 1993; Chaudhry et al, 2015a) and from a 333 bp fragment of mt-COX-1 using newly developed primers (Supplementary Table 2A) amplifying a locus within the 885 bp fragment used by Zintl et al (2014). Adapters were added to allow the successive annealing of the primers and N is the number of random nucleotides included between each specific primer to increase the variety of generated amplicons.…”