Investigating the cause of mortality of Peacock bass fish (Cichla sp.) in an ornamental fish breeding center in Tehran.

Following the observation of chronic mortality in juvenile Peacock bass fish (Cichla sp.) in an ornamental fish breeding center in Tehran city, the numbers of 10 fish were randomly sampled and transferred to the Ornamental fish clinic of University of Tehran for more investigation. before death, fish became very thin and weak and their body color faded too. The parameters of water condition were in normal range. Microscopic examination was done by Nikon E600 for better investigation. Skin scrap and gill clips showed no parasite infection. fish were necropsied after euthanasia and microscopic examination of different organs, such as liver and Spleen showed no abnormalities, but microscopic examination of digestive system showed foam-like state especially in the intestine. Further inquiries into the type of nutrition revealed that fish were fed frozen Artemia three times in a day without defrosting. This type of feeding seems to destroy the microbial flora of the digestive tract and create a foam-like state and disrupt gastrointestinal function. However, it seems that more research is needed.