CHANGES IN LEVELS OF CORTISOL, GLUCOSE AND SEX HORMONES DURING TRANSPORTATION OF SOUTHERN CASPIAN KUTUM (RUTILUS IRISII KUTUM) SPAWNERS

Physiological changes in cortisol, glucose, testosterone and 17 b-estradiol levels were studied in Rutilus frisii kutum spawners during transportation in April, 2006. The fish were held in plastic tanks in two treatments 1fish/2L and 1fish/1L sea water in several replications. Their blood was collected at 0, 10, 20, 30 and 60 min after capture. A significant increase in concentration of cortisol and glucose was found with the transport time. Initial levels of cortisol were similar in the two treatments ranging between 480.7±22.34 and 476.6±18.61 ng/ml respectively. These values increased gradually and reached a peak at the end of the transport (683±1 and 801.3±11.2ng/ml in treatments 1 and 2) with significant difference between the two (P<0.01). Glucose also changed similar to cortisol. Testosterone and 17b-estradiol concentrations decreased significantly with time. Initial levels of testosterone were 18.6±1.3 and 17.8±1.2ng/ml in the two treatments but decreased significantly at the first 10 min (P<0.01). Initial levels of 17 b-estradiol were 59.23±0.52 and 58.1±0.75 ng/ml but its levels decreased up to the end of transport. Our results clearly indicate the effect of stress during transportation.