Survey of Epidemiological of parasitic and bacterial infection in cultured fishes of Khouzestan province

Abstract

In this study which was carried out in khouzestan province , 1914 Pieces (1160 Pieces silver carp, Hypophthalmychthys molitrix; 498 Pieces common carp , cyprinus carpio; 172 Pieces Grass carp, ctenophryngodon idella and 84 Pieces Big head, Arysthychthys nobilis) from different parts of the province were examined. In three year period, 1378 to 1381, fish samples from four stations were transferred a live to the lab . Water samples also were taken and tested for some of the physicochemical factors. From a total of 1914 fish examined, 1190 showed Parasitic infestation and bacterial infections (62.2%). Infestation study, infestation with these parasites have been found: Ichthophthirius, cryptobia, Trichodina, Costia, Hexamita, Dactylogyrus, Gyrodactylus, Lernea, Bothrio cephalus, Diplostomum and Capillaria. Also some species of Aeromonas, staphylococcus, Moraxella, Pectobacterium, Flavobacterium, Citrobacteria, pasteurella, Psedomonas and Alcaligenese were identified in the samples, which normally occur in Water , but in some conditions( High pH,temperature and ammonia) could cause disease and lesions specially in gills. Infestation with dactylogyrus and Gyrodactylus was found in all four kind of fishes with different infestation rate. But the highest infestation rate with dactylogyrus was in silver carp (55.2%) and lowest in common carp (14.6%). The highest infestation rate with gyrodactylus was in grass carp (42.4%) and lowest in common carp (10.6%). Ich, Bothrio cephalus and capillalia were found only in common carp and grass carp. Infestation with adult lernea and copepodid stage of lernea had greater percentage in the gills and derm of grass carp. The data showed infestation with this parasites (specially protozoans and lernea) and bacterial infection had occurred in all seasons specially in C area.