Up-regulated Expressions of Immune Parameters, ppa, propo, sod, and hsp70 in White Shrimp Litopenaeus vannamei Reared at Unfavorable Low Salinities

The expressions of prophenoloxidase activating enzyme (ppA), prophenoloxidase (proPO) I, proPO II, and antioxidant enzymes like cytosolic manganese dismutase (cytMnSOD), mitochondrial manganese dismutase (mtMnSOD), and extracellular copper and zinc dismutase (ecCuZnSOD) as well as heat shock protein 70 (HSP70) were examined in white shrimp Litopenaeus vannamei reared for 24 weeks at salinities of 2.5%, 5%, 15%, 25%, and 35%. The expression levels of ppA, proPO I, proPO II, cytMnSOD, mtMnSOD, ecCuZnSOD, and HSP70 of shrimp reared at 2.5% and 5% were significantly higher than in shrimp reared at 15%, 25%, and 35%. We concluded that white shrimp kept under long-term culture at 2.5% and 5% were under chronic stress had up-regulated expressions of ppA, proPO, MnSOD, CuZnSOD, and HSP70 that may provide candidate biomarkers in low salinity shrimp farming.