Alteration of Phagocytic Activity of White Shrimp Litopenaeus vannamei (Boone, 1934) Reared in Isosmotic Salinity and Different Density

Effect of stocking density to assess phagocytic activity changes of white shrimp has been carried out.  White shrimp reared at a salinity of 25 ‰ with five levels of density that is 150, 250, 350, 450, and 550 shrimps/m 3 , with three replications. Phagocytic activity of hemocytes cells was analyzed at time 0, 24, 48, 96, and 144 hours after exposure to different density. The phagocytic activity data were analyzed by repeated measurement analysis of variance at the 5% significance level. Phagocytic of the density of 150, 250, and 350 shrimps/m 3 showed significant difference with a density of 450 and 550 shrimps/m 3 .  Phagocytic activity decreased fastest occur at the level densities of 450 and 550 shrimps/m 3 which is at the 24 hours after the treatment and recovery of the 144 hours, while the level of density of 350 shrimps/m 3 decreased activity at 96 hours after the treatment, and the level of density of 150 and 250 shrimps/m 3 relatively stable. These findings indicate that increasing stocking density increased phagocytosis activity disorder and disturbance density against phagocytic activity occurs faster in high population density.