Traslado de postlarvas de Litopenaeus vannamei (Boone, 1931) a diferentes tiempos, salinidades y densidades y su efecto en la supervivencia y algunos marcadores bioquímicos

The conditioning of white shrimp Litopenaeus vannamei postlarvae was evaluated during the transfer to tanks at different salinities (0, 5, 10 and 15 psu) and two densities (10 and 300 postlarvae L^-1), during three times (1, 3 and 6 h). When the transfer time increased, survival decreased in both densities and mortality rate was higher when a 300 postlarvae L^-1 density was used. A significant interrelation was found between both factors, time and salinity. In general, when salinity was lower the survival in transfer times also decreased. Survival increased with a shorter transfer time. Significant differences were found between both transfer densities when salinity increased and greater survival rate was observed at the lowest density (150 postlarvae L^-1). Biochemical markers showed significant variations on glucose concentration and phenoloxidase activity, probably due to stress conditions. A pre-acclimatizing time at a salinity level no lower than 5 psu during 48 h followed by a transfer at the same salinity, with a transfer density lower than 300 postlarvae L^-1 and a transfer period no longer than 6 h is proposed.