Notes on The Main Ecological And Nutritional Diseases In Some Water Fishs

Today aquaculture is considered an important source of productionfor meeting the world’s increasing demand for protein. Fish is an importantsource of animal protein for human consumption and their growth ratesaffected by many factors such as environmental conditions and availabilityof food. In recent years, considerable losses among farmed fish has beencaused by ammonia and nitrite poisoning. Ammonia and nitrite are thecommon toxicants in cultured systems. They are the most common waterquality problems diagnosed in aquaculture.The present study was carried out at Fish Research Center, Facultyof Veterinary Medicine, Zagazig University, to investigate:1- The effect of ammonia toxicity (environmental gill disease) and nitritetoxicity (brown blood disease) on health and growth of some rearedfish.2- The effect of excess of carbohydrate (hepatomegaly syndrome) andrancid oil (lipoid liver disease) in fish diet on health and growth inTilapia fish.3- Clinical signs, postmortem findings, haematological andhistopathological changes.I-Ammonia’toxicity: