COMBINED EFFECT OF TEMPERATURE AND SALINITY ON OXYGEN CONSUMPTION ON WHITE SHRIMP Litopenaeus vannamei POSTLARVAE

The aim was evaluated the combined effect of temperature and salinity on consumption oxygen in postlarvae (PL12) white shrimp Litopenaeus vannamei. There were realized five experiments in combination of temperature (15, 20, 25, 30 and 35 degrees C) and salinity (5, 15, 25, 35 y 45 psu). There were used for each experiment 125 bottles DBO of 300 mL, of which, 100 corresponded to the treatments (temperature x salinity) with 20 postlarvae, 20 to the whites (without postlarvae) and 5 were considered to be initial. The bottles were kept in water re-circulating with temperature controlled inside of five reservoir of glass fiber. There were realized four readings of the consumption of oxygen for a time of 1, 2, 4 and 8 h. In the first hour, there were obtained 35 readings of the consumption (25 treatments [with postlarvae], 5 whites and 5 initials). At 2 h, corresponded to 30 bottles (25 with postlarvae and 5 whites), and equally at after 4 y 8 h. The high consumption oxygen were obtained to a highest salinity and temperature, though the maximum was 14.36 (35 degrees C, 25 psu) and 13.52 (30 degrees C, 45 psu) mu g L-1 h(-1) PL and the minim in 0.07 (20 degrees C, 5 psu) mu g L-1 h(-1) PL. The oxygen consumption were significantly (P<0.05) affected by temperature, salinity and interaction of both factors. Whereas at 25 and 30 degrees C and 15 and 25 psu, showed the best oxygen consumption.