Seawater carbonate chemistry and growth, biochemical, antioxidants, metabolic enzymes and hemocytes population of the shrimp Litopenaeus vannamei

Acidification in the marine environment has become a global issue that creates serious threats to marine organisms. In the present study, we evaluated the effect of CO2 driven acidification on the shrimp Litopenaeus vannamei post-larvae (PL). L. vannamei PL were exposed to six different CO2 driven acidified seawater, such as pH 8.20 (control), pH 7.8 (IPCC-predicted ocean pH by 2100), 7.6, 7.4, 7.2 and 7.0 with corresponding pCO2 level of 380.66, 557.53, 878.55, 1355.48, 2129.46, and 3312.12 μatm for seven weeks. At the end of the acidification experiment, results revealed that survival, growth, feed index, biochemical constitutes, chitin, minerals (Na, K, and Ca), and hemocyte populations of shrimps were found to be significantly decreased in CO2 driven acidified seawater which indicates the negative impacts of acidified seawater on these parameters in L. vannamei. Further, the level of antioxidants, lipid peroxidation, and metabolic enzymes were significantly higher in the muscle of shrimps exposed to acidified seawater suggests that the L. vannamei under oxidative stress and metabolic stress. Among these various acidified seawater experiment, pH 7.6 to 7.0 produced a significantly adverse effect on shrimps. Hence, the present study concluded that the elevated level of seawater acidification can produce harmful effects on L. vannamei PL which leads to potential threats to shrimp species in the marine environment.