Phytoimmunostimulants increase of the immunity of common carp (Cyprinus carpio) against Aeromonas hydrophila infection in brackish water

Diseases are a serious problem in common carp (Cyprinus carpio) farms, and using chemicals is hazardous. It is necessary to find solutions by utilizing natural ingredients such as phytoimmunostimulants. This study aimed to determine the effect of leaf powder of mango (Mangifera indica), guava (Psidium guajava), and noni (Morinda citrifolia) as phytoimmunostimulants on the hematological and physiological of common carp. The research was carried out from January to June 2023, using a completely randomized design (CRD) with 4 treatment levels and 3 replications. The treatment levels were P0 (experimental control unit or feeding the fish with commercial fish feed only), P1 (feeding the fish with commercial fish feed containing noni leaf powder of 1.5 g/100 g), P2 (feeding the fish with commercial fish feed containing guava leaf powder of 1.5 g/100 g), and P3 (feeding the fish with commercial fish feed containing mango leaf powder of 1.5 g/100 g). The fish were challenged with Aeromonas hydrophila bacteria on the 30th day. The hematological and physiological profiles of the fish were measured at 0, 30, and 45 days. The treatment using guava leaves showed the most promising results for total levels of erythrocites, hemoglobin, hematrocit, blood glucose and survival rate. The use of guava leaves provided the best immune response and could be developed as part of the diet in the future.