Epidemiological, multidisciplinary analysis using molecular, morphological, and immunological approaches in the Diplostomasis infections in Oreochromis niloticus

Abstract

We aim to describe the epidemiological, multidisciplinary analysis using molecular, morphological, and immunological approaches in the Diplostomasis infections on Oreochromis niloticus in different localities in Egypt. This was a descriptive retrospective study that collected 470 Nile tilapia samples from 4 governorates, in Egypt during the period from January 2022 and December 2023. The variables studied were epidemiological, molecular, morphological, and immunological approaches. For the isolates D. ardeaeand D. spathaecum, entirely sequences of the ITS2 region genes and partial sequences of the cytochrome C oxidase subunit 1 (Cox1) "barcode" area was amplified. Cox1 partial sequences were utilized to analyze the haplotype diversity and potential host-associated structures of the most prevalent parasite species, as well as for the genetic determination of isolates. New primers were designed for the amplification of the investigated genes. Therefore, this study aimed to detect various pro-inflammatory cytokines in fish infected with Diplostomum MCs using an immunological approach. (IFN-γ, IL-2, IL-6, TNF-α, & TNF-β) in the infected muscles contain Diplostomum sp. using quantitative real-time PCR (qRT-PCR). In addition, histopathological alterations of EMCs induced Zenkers necrosis and mononuclear inflammatory cells of fish muscle bundles response with muscular inflammation of infected fishes. In Egypt, an epidemiological study of two Diplostomid trematodes either metacercarial (D. spathaceum) in the eye and encysted metacercarial (D.ardeae) infections in the muscles of O. niloticus fish from four geographically different areas. The first genetic characterizations and immunological approach of two Diplostomum spp.; D. spathaceum and D.ardeae were all deposited in GenBank under the accession numbers (OR763842.1) and (OR755782.1).