The whiteleg shrimp is the most produced aquatic animal globally, reaching 7.36 million tons in 2023 (FAO). Despite promising growth, whiteleg shrimp farming faces sustainability challenges such as nutrient sourcing (including phosphorus), environmental impact, and diseases like acute hepatopancreatic necrosis disease (AHPND) caused by Vibrio parahaemolyticus. Inorganic feed phosphates (IFP) are used to meet shrimp phosphorus (P) needs, but data on requirements and the efficiency of available IFPs are limited. It was observed that IFPs may modulate the innate immune response in fish and shrimp. Our study had two objectives: 1) compare the effects of different IFPs on shrimp growth and survival during a production cycle, and 2) evaluate their impact on shrimp immune response and survival against Vibrio parahaemolyticus.
In the growth trial, shrimps of 1.7g were distributed into 35 hapa nets and fed with a control diet (CTRL) or diets supplemented with IFPs: dicalcium phosphate (DCP), monocalcium (MCP), magnesium phosphate (MgP), monoammonium phosphate (MAP), monosodium phosphate (MSP), and a new IFP, calcium humophosphate (CHP). After 90 days, growth, survival rates, total hemocyte count (THC), and lysozyme activity (LA) were assessed. For the immune challenge trial, shrimp were fed experimental diets for 14 days before injection with V. parahaemolyticus, followed by daily mortality tracking and further analysis on immune parameters and histology of hepatopancreas.
Results revealed that IFP type significantly affects shrimp growth and survival, with MSP and MAP providing the best performance, followed closely by CHP (p < 0.005). DCP supplementation had minimal effects compared to CTRL. IFP sources also modulated immune parameters, enhancing THC for MCP, MAP, CHP, and MSP (p = 0.032) which increased also LA (p = 0.018). In the immune challenge, shrimp fed IFPs showed a trend of improved survival rate (p = 0.07), highlighting IFPs’ potential contribution to immune resistance. Moreover, IFPs significantly affected Vibrio sp. count in the hepatopancreas before challenge (p = 0.022). Overall, this study demonstrates that IFP type significantly influences shrimp performances and potentially its susceptibility to Vibrio sp. infection.