This work aimed to evaluate Nannochloropsis spp. as feed additive in the diet of Pacific white shrimp for their effect on midgut microbiology, thermal shock resistance and immunological parameters. Initially, the digestibility of the microalgae meal was assessed, and the apparent digestibility coefficient (ADC) was determined. The ADC was, in general, high in lipids (78.88%) and eicosapentaenoic fatty acid (73.86%). Then, Nannochloropsis spp. were included in diets at four levels (0, 0.5, 1 and 2% inclusion). The shrimp were reared in 500 L clear water tanks containing 20 shrimp per tank with an initial weight of 6.05 ± 0.06 g and fed four times a day. Shrimp fed with supplemented diets containing Nannochloropsis spp. (0.5 and 2%) presented higher resistance to thermal shock when compared to the non-supplemented group (control). Shrimp fed with 1 and 2% of algae inclusion had a higher production of reactive oxygen species (ROS) when compared to other treatments. No statistical difference was observed in the immunological parameters and microbiology of the intestinal tract. Thus, the inclusion of Nannochloropsis spp. in shrimp diets at 0.5 and 2% levels increases resistance to thermal shock and ROS production in shrimp.

Traditional shrimp maturation uses high water exchange, conflicting with sustainable farming and biosecurity, although broodstock production systems have been updated by the adoption of closed-cycle production. So, this study evaluated BFT for Penaeus vannamei broodstock maturation, comparing it against a conventional system. The research compared two treatments, BFT and CW, in three replicated tank systems. Each experimental unit was a circular fiberglass tank with 5.63 m³ working volume. BFT tanks involved a 3.12 m² mobile triangular cage for viewing and capturing mated females. Parameters monitored included water quality, reproductive performance and hemato-immunological responses. The BFT system resulted in greater water quality stability, significantly lower water consumption, and lower Total Ammonia Nitrogen (TAN) concentrations, indicating efficient ammonia recycling. Also, reproductive performance and most hemato-immunological parameters did not differ significantly between treatments. Although CW showed slightly higher broodstock survival and sperm viability, BFT males exhibited a significantly higher Total Hemocyte Count (THC). Overall, BFT is suitable for sustainable P. vannamei broodstock maturation, as it promotes stable environmental conditions without compromising reproductive or immunological performance. Further research is recommended, particularly regarding effects of zero-water-exchange on male shrimp and improvements on capture structures.