عنوان مقاله [English]
Ammonia is the most toxic compounds of nitrogen which is a serious problem in the aquaculture industry. In this study, we investigated the effect of sub lethal concentration of ammonia on the activity of tissue enzymes and some blood biochemical parameters and recovery ability of common carp. The total of 80 common carps (mean body weight of 50±4.5 g) was divided randomly into four groups of 20 each. Group I: 96 hours under the expose of ammonia, Group II: 96 hours under the expose of ammonia and serving a 24-hour recovery period, Group III: 96 hours under the expose of ammonia and serving a 7-day recovery period and Group IV: were reared in normal freshwater and served as the control. From each group to assess the biochemical and enzymatic factors of tissue and blood samples were collected. The results showed that ammonia significantly increased the activity of enzymes AST, ALP and LDH in both tissues But significant increase in ALT activity were observed in any of these tissues (P<0.05). After seven days of enzyme activity was significantly decreased in the gill tissue And this process were observed in liver enzymes AST and LDH but ALP activity after seven days of recovery, still significantly higher than the control group(P<0.05). Ammonia is also significant decreases in serum protein while the amount of cortisol and glucose increased. All of these factors have returned to normal after a seven-day recovery period. The ammonia can cause changes in the activity of metabolic enzymes in the liver and gill damage to the tissues and some biochemical parameters in serum of common carp and proper conditions (absence of ammonia) can be significant improvement in the texture of the fish.