Influence of Water Quality on the Seasonal Infestation of the Nile Tilapia with Gill Parasites in Different Localities Along Rosetta Branch, the River Nile.

The present study was designed to reveal the relative impact of water quality changes induced by the climate’s influence and some waste discharge on the existence and prevalence of some gill parasite species in the Nile tilapia inhabiting Rosetta Branch, the River Nile. Both fish (1600 Nile tilapia fish) and water samples were randomly collected seasonally from four sites (El-Kanater El-Khayria, El-Qatta, Tamalay, and Kafr ElZayat) along the Rosetta Branch of the Nile, which receives some types of wastewater. Parasitological examination of fish revealed the presence of Trichodina sp., Ambiphyra sp., Cichlidogyrus tilapiae, the encysted metacercaria of Clinostomum phalacrocoracis, and the larval stage of the freshwater mussels, Glochidia. The highest parasite prevalence was recorded at Kafr El-Zayat station, followed by El-Qatta and Tamalay. On the other hand, the autumn season recorded the highest parasitic prevalence, followed by winter, summer, and spring. The histological examination of the gills of the infected fish revealed severe histological alterations and the presence of different histozoic parasites. The most significant water parameters influencing the parasitic prevalence were temperature, pH, DO, BOD, and ammonia. The outcomes reveal that water parameter, temperature, pH, DO, BOD, and TAN are important factors affecting the different parasite prevalence values of the infected tilapia fish. [ABSTRACT FROM AUTHOR]

Copyright of Egyptian Journal of Aquatic Biology & Fisheries is the property of Egyptian Society for Fisheries Development & Human Health and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)