Studies on Parasitic Infestations in Some Cultured Marine Fishes

Abstract

The present study was carried out on (360) cultured marine fishes (120 sea bass Dicentrarchus labrax, 70 sea bream Sparus aurata, 60 Grey mullet Mugil cephalus, 60 Thinlip grey mullet Liza ramada, and 50 European eel Anguilla anguilla) collected from private fish farms located in Diba triangle, Damietta governorate, over different year seasons. Collected fish samples were subjected to clinical, post-mortem as well as parasitological examinations. Water samples were also collected from the same farms and were examined for some physical and chemical parameters. The results of the preset study could be summarized as follow:  The total prevalence of parasitic infestations of examined fishes was 65.3%. The heighst prevalence was shown in D. labrax (84.2%) followed by S. aurata (78.6%), M. cephalus (71.7%), L. ramada (33,3%) and A. anguilla (18,0%).  Collected Examined fish suffered from restlessness, gasping of air, rubbing body against hard objects, jumping from water, hemorrhagic skin and fins, detachment of scales and excessive mucous secretion on the body and gills. Fishes with internal parasites showed emaciation, anemic and off food.  The post mortem finding of examined fishes revealed paleness of gills and friable pale liver.Some fishes revealed congestion and haemorrhge in the gastrointestinal tract. No specific post-mortem changes appeared in examined A. anguilla.