Ecological studies on the helminth parasites of catfishes Bagrus spp. (Bagridae) and Chrysichthys auratus (Claroteidae) inhabiting Damietta branch, River Nile, Egypt

Abstract

The results of a survey on the helminth parasites of the catfishes Bagrus spp. Forsskål, 1775 and Chrysichthys auratus Geoffroy,1809 inhabiting Damietta branch of the River Nile at Mansoura city, Dakahlia Governorate, Egypt, have been demonstrated. During the period of March 2020 to February 2021, five species were detected from Bagrus spp. and represented by one monogenean Quadriacanthus bagrae from the gills, three digeneans Acanthostomum absconditum, Acanthostomum spiniceps and Haplorchoides cahirinus and a single nematode species Capillostrongyloides fritschi from the intestine. Only one monogenean species Protoancylodiscoides mansourensis was detected from the gills of Chrysichthys auratus. Except for a few months, most monogeneans, digeneans and nematodes of Bagrus spp. and C. auratus were recorded in all months of the year. The digeneans A. absconditum, A. spinicips, and H. cahirinus are eudominant and A. absconditum was the most dominant while the nematode C. fritschi is subrecedent. In Bagrus spp., the digenean parasites attained the highest prevalence over the monogeneans and nematode parasites throughout the year (77.7%). There was a definite seasonal change in the studied helminths, but no general common trend or pattern was observed. Most helminth parasites showed a higher prevalence in male fishes than females while they attained a higher abundance in females than males. There was a significant difference in the mean prevalence as well as in the mean intensity of most examined parasite species in male fishes and females but a significant difference in the mean abundance of males and females was only recorded for the digenean parasites. Most parasites showed a higher prevalence as the condition factor of the host increased.