Effect of temperature and salinity on larval survival and development of Litopenaeus vannamei

Objetive. The combined effect of salinity (25, 30, 35, and 40psu) and temperature (25, 30, and 35 degrees C) was evaluated on survival and development from nauplii V (NV) larvae until postlarvae (PL1) of Litopenaeus vannamei. Materials and methods. Four replicates were applied to each combination of salinity and temperature. The larvae were placed in 12 L beakers a density of 100larvae/L. Salinity was increased dissolving commercial salt without iodine, into marine water, whereas fresh filtered tap water was used to decrease the salinity from seawater. The NV were adapted at 35psu and 30 degrees C during 30 minutes. Thereafter, were transferred at each experimental combination of salinity and temperature. Every 24 h, samples of larvae were obtained to determine in vivo their stage of development and survival. All data were analyzed using a two-way ANOVA. Results. Survival and larval development were significantly (p < 0.05) affected by salinity, temperature and interaction of both factors. Maximum ultimate survival to PL1 was obtained at 30 degrees C and 30psu (82.2%) followed by 30 and 35 degrees C at 25psu (71.5 y 71.6%). The highest development at PL1 was found at 30 degrees C and 30psu (6.76). Larval development during experiment was lower at 25 degrees C as compared to 30 and 35 degrees C, regardless of the salinity levels. Conclusions. The most adequate conditions for survival and larval development were obtained between 30-35 degrees C and 25-30psu.