Growth performance, production and economic viability of Indian white shrimp (Penaeus indicus H. Milne Edwards) fed with varying dietary protein levels.

The growth efficiency, productivity and economic viability of Indian white shrimp (Penaeus indicus) fed with diet containing 40% (CPhigh) and 34% (CPlow) crude protein (CP) levels were determined in a 90‐day grow‐out culture trial. Growth parameters including average body weight (ABW), specific growth rate (SGR), survival and feed conversion ratio (FCR) were not statistically different. CPlow had lower overall shrimp production (797.53 kg/ha, DOC 90), but was not significantly different from CPhigh (843.78 kg/ha, DOC 90). The mean values for the water parameters of both treatments, such as DO, pH, salinity, temperature, TAN, NO2‐N, NO3‐N and PO4‐P, also showed no significant differences. However, the TAN values of CPhigh were consistently higher from day of culture (DOC) 63 and increased significantly (p =.048) at DOC 90. Furthermore, the total bacterial and Vibrio counts in both treatments were not significant throughout the culture period. The economic analysis revealed that CPlow obtained higher net profits (6093 USD/ha/year), return on investment (72%) and discounted benefit–cost ratio (1.73). The current study found that feeding a low protein diet to P. indicus is economically viable and profitable and results in improved growth efficiency and productivity while also improving water quality and lowering nitrogen discharge. [ABSTRACT FROM AUTHOR]