White shrimp (Litopenaeus vannamei) is one of the shrimp species that is widely cultivated because of economic value and one of the national superior commodities. Salinity is one that influences the shrimp, if it does not fit the shrimp, it will stress and cause an outbreak of disease, it is easier to infect shrimp, one of them is white feces syndrome (WFS). The use of squid ink is one of the solutions used to inhibit WFS because squid ink contains oleic acid which can kill bacteria directly by damaging the cell wall. The purpose of this study was to determine the effect of squid ink extract (Loligo sp.) on histopathology of hepatopancreas and gut, also digestive enzymes in white shrimp (L. vannamei) infected with WFS in different media salinity.
The effect of salinity test was carried out by infecting 30 DOC (Day of Culture) white shrimp with 106 CFU/mL V. harveyii using immersion method, addition of blue green algae (BGA), and continued with tissue histology. Using 3 treatments, 25 ppt (A), 27 ppt (B), 30 ppt (C), and negative control (33 ppt, healthy shrimp). 8 ppm squid ink extract was add to the feed for 2 weeks treatment. The best media salinity was 27 ppt which affected the histopathology of the white shrimp hepatopancreas, while it didn’t affect the histopathology of gut tissue. The average increase in digestible enzime was higher in 27 ppt than other treatments, protease enzyme activity was 0,378 U/mL, amylase enzyme was 4,029 U/mL, and lipase enzyme was 3,613 U/mL. The highest survival rate was 85% in 27 ppt salinity. Conclusion from this research was using 27 ppt salinity and squid ink extract for white shrimp (L. vannamei) with WFS case.