The effect of the addition of Bacillus probiotic during larvae and postlarvae culture of the white shrimp Litopenaeus vannamei was examined in three separate experiments: (I) Nauplius 4-5 to Zoea 3 , which were exposed to probiotic in the water (P w ), only in the microalgae (P m ), in the water and microalgae (P wm ) and a control with no probiotic (C); (II) Mysis 1 to Mysis 3 , which were exposed to probiotic in the water (P w ), only in Artemia (P a ), in the water and Artemia (P wa ) and a control (C); (III) PL 1 to PL 10 , which were exposed to similar treatments for mysis experiment. The use of probiotic Bacillus spp. resulted in an increase in the survival and growth of zoea and mysis phases, especially when the probiotic was added only in the water. For postlarvae, the use of the probiotic had no influence on the zootechnical parameters, however, there was a reduction in the count of presumptive Vibrio both for water and shrimp.

Experiments were conducted to evaluate different prophylactic methods to control the bacterial load in brine shrimp, Artemia, hatching. The first experiment evaluated three treatments to control Vibrio spp. during the Artemia hatching: microalgae (Chaetoceros calcitrans), probiotic (Bacillus spp.), and antibiotic (Florfenicol). In the second experiment, Artemia metanauplius were enriched in distinct treatments with C. calcitrans, probiotic, and emulsion rich in docosahexaenoic and eicosapentaenoic fatty acids. Enriched Artemia metanauplius and nauplii (control) were offered to white shrimp, Litopenaeus vannamei , postlarvae (PL 7 -PL 19 ). Presumptive Vibrio were quantified in Artemia, PL, and rearing water. Microalgae and probiotic were effective to control Vibrio spp. in Artemia nauplii. The enrichment process increased the Artemia bacterial load but did not affect Vibrio load in L. vannamei .