Astaxanthin krill oil enhances the growth performance and fatty acid composition of the Pacific whiteleg shrimp, Litopenaeus vannamei, reared under hypersaline conditions

Hypersalinity culture of marine shrimp can lead to poor growth and feed efficiency. This study evaluated the effect of dietary supplementation of three oil sources (krill, fish and soybean) on the growth of Litopenaeus vannamei reared under high salinity. Shrimp of 2.79 +/- 0.60g were reared for 64days under isosmotic (ISO, 23 +/- 1.2g/L) and hyperosmotic (HOS, 44 +/- 2.0g/L) conditions. Diets varied in their fatty acid composition: Control, 35g/kg of the diet (as fed basis) soybean oil; Fish, 27g/kg fish oil and 10g/kg soybean oil; Krill, 48g/kg krill oil and 4g/kg soybean oil; Krill-, 15g/kg krill oil and 21g/kg soybean oil; Krill+, 55g/kg krill oil and 4g/kg soybean oil. At harvest, Krill diet promoted the fastest shrimp growth (1.01 +/- 0.01g/week) and body weight (11.97 +/- 2.01g), regardless of water salinity. There were no significant differences in shrimp survival (93.4 +/- 5.07%) and yield (554 +/- 68.5g/m(2)) among different diets. Shrimp fed Fish, Krill and Krill+ had higher concentrations of PUFA compared to those fed Control and Krill- diets.