Parasitological and Comparative Pathological Studies on Monogenean Infestation of Cultured Sea Bream (Sparus aurata, Spariidae) in Egypt.

Abstract

This investigation was realized between December 2012 to November 2013. A total of 400 Sea bream (Sparus aurata) were sampled with history of loss of appetite and sluggish movement with increased breathing frequency, were investigated in terms of monogenean parasites .The prevalence, seasonal dynamics, mean intensity as well as the histopathological influence of the detected monogeneans were estimated. The standard parasitological methods were used in the survey and yielded four monogenean species on the Sea bream gills: Furnestinia Echeneis (58.59% of invaded fish), Encotyllabe spari 32.81%, Sparicotyle chrysophrii 25.78% and Choriocotyle chrysophrii 17.19%. The total prevalence was 32% and the highest rate was recorded during summer. With the exception of Encotyllabe spari, the detected parasites are new records for the monogenean fauna of Egypt (new geographical record) and also Sea bream (Sparus aurata) is a new host record for the monogenean Choriocotyle chrysophrii. Histopathological examination revealed different pathological changes in the affected branchial tissue. The lesions were depended on the type of the detected monogenea. Necrosis of the gill lamellar epithelium, hyperplasia of mucous secreting cells and focal areas of denuded epithelium were the most common lesions noticed at the sites of parasites attachment.