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Biology subjects

Shehzad, W.

Publications and source records attributed to Shehzad, W..

2 recordsLinked to original sources

Molecular characterization of Fasciola gigantica in Punjab, Pakistan to infer the dispersal route among the neighbouring countries of the Indian subcontinent

Fasciola gigantica is considered to be a major pathogen causing fasciolosis in the Indian subcontinent, resulting in millions of dollars production losses to the livestock industry. To understand the dispersal origin and the spread patterns of F. gigantica is important for preventing the disease. A total of 53 Fasciola flukes collected from buffalo and goat in the Punjab province of Pakistan, were identified as F. gigantica based on the multiplex PCR for the phosphoenolpyruvate carboxykinase (pepck) and the PCR-restriction fragment length polymorphism (RFLP) for DNA polymerase delta (pold). A significant genetic difference between F. gigantica from buffalo and goats in Pakistan was indicated by the genetic analysis of two distinct mitochondrial markers [NADH dehydrogenase subunit 1 (nad1) and cytochrome C oxidase subunit 1 (cox1)]. Phylogenetic analysis of the seventeen nad1 haplotypes of F. gigantica from Pakistan with those in neighbouring countries of the Indian subcontinent revealed that all the haplotypes were clustered in haplogroup A. Fasciola gigantica with the eight haplotypes might be expanded in Pakistan from Indian origin, along with the migration of the domestic animals, since they were related to Indian haplotypes. In contrast, the remaining nine haplotypes were not shared with any neighbouring countries, suggesting independent origin, or possibly come from neighbouring Middle East countries. Our study provides a proof of concept for a method that could be used to investigate the epidemiology of F. gigantica regarding the development of sustainable parasite control strategies.

genetics↗

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

Fasciola gigantica liver flukes are responsible for over 3 billion US dollars of production loss annually in farmed livestock and cause widespread zoonotic disease. Nevertheless, the understating of the emergence and spread of the trematode species is poor. The multiplicity of F. gigantica infection and its spread is potentially influenced by multiple factors, including the abundance of suitable intermediate hosts, climatic conditions favoring the completion of the parasites lifecycle, and translocation of infected animals or free-living parasite stages between regions. Here we describe the development of a tremabiome metabarcoding sequencing method to explore the numbers of F. gigantica genotypes per infection and patterns of parasite spread, based on genetic characteristics of the mitochondrial NADH dehydrogenase 1 (mt-ND-1) locus. We collected F. gigantica from three abattoirs in the Punjab and Balochistan provinces of Pakistan, and our results show a high level of genetic diversity in 20 F. gigantica populations derived from small and large ruminants consigned to slaughter in both provinces. This implies that F. gigantica can reproduce in its definitive hosts through meiosis involving cross- and self-breeding, as described in the closely related species, Fasciola hepatica. The genetic diversity between the 20 populations derived from different locations also illustrates the impact of animal movements on gene flow. Our results demonstrate the predominance of single haplotypes, consistent with a single introduction of F. gigantica infection in 85% of the hosts from which the parasite populations were derived. This is consistent with clonal reproduction in the intermediate snail hosts.

genetics↗