Cultivo a baja salinidad de postlarvas de Litopenaeus vannamei con diferentes relaciones de K+/ Na+

An experiment was designed totally randomized to study the influence of different rate of Na+/K+ (5, 30, 55, 70, 95 and 120). Massive mortality was presented to the sixth day of the treatments I and III (Na+/K+=5 and Na+/K+=120), to the seventh day the treatment V (Na+/K+=95) and to the eighth day of the treatment IV (Na+/K+=70). The treatments II and III (Na+/K+=30 and Na+/K+=55 respectively) they stayed in the time, when indicating a bigger tolerance of the postlarvae in these ranges of Na+/K+; however, the mortality of the treatment II were significantly bigger (p <0.01) that in the treatment III, in which 90-100% survival was observed. The results indicate a better physiologic answer of L. vannamei postlarvae to relationships Na+/K+ among 8-48, with a good of 30-32, that which has implications for the handling and preparation, of the water of culture of low salinity (up to 2 ups) during the nursery phase and growth out.