Determination of Acute Toxicity of Ammonia(LC50 96h, N-NH4) and Effects on Histopathology Status Gill ‚Kidney and Liver of Acipenser stellatus (Acipenser stellatus Pallas, 1811)

Rising ammonia water is one of the major problems in aquaculture that its effects are not yet clear. The purpose of the present study is to determine the acute lethal concentration of ammonia and its effects on three gill tissue, liver and kidneys of fish species Acipenser stellatus weighted average of 3 grams in lab situation value. The tests were done on 7 cases and 3 repetitions and a whole number of 10 fish by stagnant water method for 96 hours. Fish were exposed to different whole Ammonia concentrations which were 0, 5, 6.23, 7.76, 9.66, 12.04 & 15 mg in liter for baby Acipenser stellatus. First, the amount of Ammonia LC50 in 24, 48, 72 & 96 hours was gained, this was calculated for baby Acipenser stellatus respectively 14.0249, 10.2164, 7.1531, 6.0353 mg in liter whole Ammonia. After finding LC50 amounts, we chose one low level of LC50 which is 25% concentration and one high level of LC50 which is 75% concentration and the test was repeated by 4 cases and 3 repetitions. Concentration range for this material was 1.508, 3.017 & 4.526 mg in liter whole Ammonia. The results showed that in gills, liver and kidney tissue destruction was observed after exposure to ammonia. Generally, the most injuries are observed in these fish's gill.