Increasing stocking densities affect hemato-immunological parameters of Nile tilapia reared in an integrated system with Pacific white shrimp using biofloc technology

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.

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ADDITION OF Aurantiochytrium sp. MEAL IN THE DIET AFFECTS IMMUNITY AND THERMAL SHOCK RESISTANCE OF THE PACIFIC WHITE SHRIMP

Boletim do Instituto de Pesca ◽

10.20950/1678-2305/bip.2021.47.e631 ◽

2021 ◽

Vol 47 ◽

pp. e631

Author(s):

Jamilly Sousa ROCHA ◽

Mariana SOARES ◽

Ariane Martins GUIMARÃES ◽

Delano Dias SCHLEDER ◽

Walter Quadros SEIFFERT ◽

...

Keyword(s):

Thermal Shock ◽

Water System ◽

Pacific White Shrimp ◽

White Shrimp ◽

Feed Additive ◽

Immunological Parameters ◽

Good Utilization ◽

Apparent Digestibility Coefficient ◽

The Pacific ◽

Docosahexaenoic Fatty Acid

This paper reports the evaluation of digestibility, immunological parameters, and resistance to thermal shock at low temperature in Litopenaeus vannamei fed diets with diferent Aurantiochytrium sp. meal additions (0; 0.5; 1 and 2%). First, the apparent digestibility coefficient of the ingredient was determined. The digestibility of the microalgae meal was high for protein (74.90%); around 60% for lipids, and for docosahexaenoic fatty acid (DHA) it was 55.61%. After, shrimp rearing with the feed additive was carried out in a clear water system, containing 25 shrimp (initial weight: 4.89 ± 0.27 g) per 400 L tank. Feeding occurred four times a day. After a three-week period, immunological parameters were evaluated and thermal shock was performed. Animals fed 0.5% and 2% of the microalgae Aurantiochytrium sp. showed higher survival to thermal shock. In immunological analyses, the serum agglutiniting titer was higher (p <0.05) in the 0.5 and 2% additions of the microalgae meal, and the phenoloxidase activity (PO) was higher in the 1% addition (p <0.05). It is concluded that there is good utilization of the nutrients of Aurantiochytrium sp. meal by L. vannamei and its addition to the diet (0.5 and 1%) increased shrimp resistance to thermal shock.

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