study on stress indices in the acute and sub-acute response of carassius auratus to the aquatic pollutants

to evaluate the levels of cortisol, glucose and other possible indicators of goldfish, carassius auratus, in response to stress, in the first experiment, bisphenol a (0.5 mg/l), naphthalene (200 μg/l) and butachlor (60%) (0.28 µg/l) were added to the aquariums water for two weeks. in the second experiment, intra-peritoneal injections of  bisphenol a, naphthalene and butachlor, with dose 50 mg/kg, 50 mg/kg, 20 μl on the body weight of fish were performed. on the fifth day and the end of the experiment (fifteenth day) as well as 48 hours after injection, blood sampling from caudal vein was taken and levels of cortisol, glucose, total protein and inorganic phosphorous in blood plasma were measured. the results showed that the cortisol and glucose levels on day 5, was a significant difference between control and butachlor treatments (p <0.05) and this difference was not observed in the other treatments. in addition, there were not statistically significant differences in the plasma levels of cortisol, glucose, total protein and inorganic phosphorus in fish under stress and control samples at the end of the experiment (fifteenth day) and injected samples (p>0.05). comparing the results of the analysis of blood plasma in the fifth and fifteenth days of experiment, it was found that levels of cortisol and glucose in the treatment butachlor had significantly different together within two periods (p<0.05). in general, it seems that the goldfish can be resistant to aquatic pollutants and respond time to the environmental stresses is between 3 to 5 days.