Immunomodulatory Effect of Nigella Sativa Seed Powder on Labeo catla and Its Resistance against Aeromonas hydrophila

Abstract

This study aimed to investigate the immunomodulatory effect of black cumin (Nigella sativa) seed on Labeo catla and its resistance to Aeromonas hydrophila. A feeding experiment was conducted using black cumin seed powder (BCSP) diets at four concentrations: treatment T0 (0% BCSP), T1 (1% BCSP), T2 (2% BCSP), T3 (3% BCSP), and T4 (4% BCSP). Ten L. catla seeds (average weight 1.14±0.05 g) were stocked in 20 plastic aquarium tanks. At the end of the 45-day feeding trial, the immune parameters in the 4% BCSP treatment showed higher values for respiratory burst activity (RBA), total erythrocyte count (TEC), and total leucocyte count (TLC), with values of 0.56± 0.024, 1.99±0.04, 28.9±0.38. Growth performance indicators, including body mass and weight gain, specific growth rate (SGR), feed conversion ratio (FCR), and survival rate (SR), demonstrated significant differences in the 4% BCSP treatment. At the end of the 45-day experimental period, 10 fish from each triplicate treatment tank were injected with Aeromonas hydrophila suspension (1 x 106 cells/ml). During the 10-day challenge study, fish fed 3% and 4% BCSP showed significantly lower mortality. Statistical analysis revealed no significant difference between treatments T3 and T4, indicating that the lower dose is more cost-effective as a feed supplement. Therefore, the incorporation of 3% black cumin seed powder (BCSP) into the diet is considered optimal for enhancing immune response and growth performance.