Synergistic Effects of Phytogenic Blends on Growth Performance, Nutrient Utilization, Digestive Enzyme Activity and Haemato-immunological Response of Nile Tilapia (Oreochromis niloticus) in Natural Pond Ecosystem

Abstract

Present experiment was carried out during July to October, 2023 at the pond facilities of the Faculty of Fishery Sciences of West Bengal University of Animal and Fishery Sciences, Kolkata, India to evaluate the efficacy of two phytochemical formulations in Nile tilapia fingerlings. Medicinal herbs and their extracts were increasingly favoured in aquaculture due to their immunostimulatory, anti-inflammatory, and growth-promoting properties. A 90-day pond trial was conducted using a completely randomized design with three dietary groups in triplicate. In control there was no additive. In first treatment group a mixture of garlic, methi, and eucalyptus leaf and in second treatment group a blend of thyme, eucalyptus, and clove essential oils were included at 0.5 g kg^-1. Assessments included growth performance, feed utilisation, digestive and metabolic enzyme activities, haemato-immunological assays, and serum biomarkers. Results indicated that these phytogenic blends significantly influenced growth trajectories. The treatment group 1 exhibited superior body weight gain, nutrient utilization, and respiratory burst modulation, suggesting a synergistic effect of the herbal combination. Body weight gain (g), specific growth rate and feed conversion ratio values in group 1 were 37.23, 1.68 and 0.75 in comparison to group 2 showing the values 25.41, 1.40 and 1.06, respectively. These findings demonstrated that a dietary phytochemical formulation of garlic, methi, and eucalyptus positively influenced physiological robustness and supported sustainable fish production.