Blue lotus (Nymphaea nouchali) flower and leaf supplements enhance growth and hemato-immunological parameters in Indian major carp (Labeo rohita) juveniles

The enhancement of both disease resistance and growth performance are essential for successful fish production and the use of dietary medicinal herbs can be used as natural immunostimulants as well as growth promoter in fish. Consequently, a 45-day feeding experiment was conducted to explore the effect of dietary blue lotus (Nymphaea nouchali) leaf (BLL) and blue lotus flower (BLF) on growth and haemato-immunological parameters in Labeo rohita fingerlings and reported for the first time. Two hundred fingerlings (average weight 18.5 ± 0.1 g) were randomly assigned to five treatment groups in quadruplicate. Five purified diets (35% CP) were made with varying degrees of either blue lotus leaf (BLL) or flower (BLF) inclusion viz.T1 (Control - 0%), T2 (0.2% BLL), T3 (0.4% BLL), T4 (0.2% BLF) and T5 (0.4% BLF). Weight gain (percent) and SGR increased significantly (P < 0.05) after inclusion at graded levels, but other measures such as FCR, PER, HSI, and GSI showed no discernible changes (P > 0.05). Total protein, globulin, and glucose concentrations in the serum showed a significant difference (P < 0.05). Serum total protein and globulin levels were significantly (P < 0.05) higher in the T5 group, whereas serum glucose levels, declined significantly (P < 0.05) compared to contol. There was a significant (P < 0.05) rise in WBC count, but no significant (P > 0.05) changes in haemoglobin (Hb) and RBC count. Overall, the findings of the results conclude that the dietary supplementation of blue lotus leaves and flowers can increase growth and enhance better immune response in Indian major carp, L. rohita juveniles.