Serum Electrolytes of Wild and Captive Bluefin Tuna(Thunnus thynnus L.) in Turkish Seas

The aim of the study was to investigate serum electrolytes-sodium (Na), potassium (K), chloride (Cl), Calcium (Ca), Magnesium (Mg) and phosphorus (P) in wild and captive Bluefin Tuna (BFT) in the Eastern Mediterranean. For this purpose, 127 individual samples consisting of 62 wild and 65 farmed samples were chosen. The wild fish was obtained from Antalya Bay and the captives were taken from a tuna farm in Ildir Bay (Izmir) during the spring. The mean serum electrolyte levels of wilds were found to be as follows: 209.84 mmol L-1, 9.84 mEq L-1, 183.47 mmol L-1, 7.49 mEq L-1, 7.83 mg 100 mL-1, 5.03 mg 100 mL-1. Analogous data for the captive fish were detected as follows: 205.85 mmol L-1, 6.46 mEq L-1, 180.45 mmol L-1, 7.19 mEq L-1, 6.68 mg 100 mL-1, 3.32 mg 100 mL-1. In comparing the wild with the captive fish, the K, Mg and P differences were significant, except for Na, Ca and CL (p<0.05). On the other hand in terms of gender, the mean serum electrolyte levels of 30 wild and 30 captive individual female BFT were determined, respectively to be as follows: Na, 205.58, 201.47 mmol L-1; K, 8.73, 6.38 mEq L-1; CL, 186.25, 182.63 mmol L-1; Ca, 7.19, 6.71 mEq L-1; Mg, 5.92, 6.52 mg 100 mL-1; P, 4.43, 3.06 mg 100 mL-1. In addition, these parameters for 32 wild and 35 captive male specimens were detected, respectively to be as follows: Na, 214.09, 210.23 mmol L-1; K, 10.95, 6.54 mEq L-1; CL, 180.68, 178.27 mmol L-1; Ca, 7.78, 7.67 mEq L-1; Mg, 8.47, 6.83 mg 100 mL-1; P, 5.62, 3.58 mg 100 mL-1. According to gender, the differences in K, Mg and P in wild vs. captive female and wild vs. captive male samples were significant (p<0.05). However, the Na, Cl and Ca differences were not significant between wild and captive female and male specimens (p>0.05).