Dietary Application of Medicinal Plant-derived Prebiotics from Althaea officinalis and Hylocereus undatus on Growth Performance, Immunity, and Disease Resistance in Freshwater Fish Labeo rohita

Abstract

Plant-derived prebiotics from Althaea officinalis and Hylocereus undatus may serve as sustainable alternatives to antibiotics by enhancing growth, immunity, antioxidant defense, and disease resistance in Labeo rohita against Aeromonas hydrophila infection.The present study investigated the effects of plant-derived prebiotics obtained from Althaea officinalis and Hylocereus undatus on growth performance, feed utilization, hematological responses, immunity, and disease resistance in Labeo rohita. These medicinal plants are rich sources of bioactive compounds including polysaccharides, mucilage, oligosaccharides, flavonoids, phenolics, and dietary fibers that possess potential prebiotic and antioxidant properties. Five experimental diets consisting of one control diet and four prebiotic-supplemented diets were formulated and administered to fish for 10 weeks under controlled laboratory conditions. Significant improvements (p < 0.05) were observed in final body weight, weight gain, specific growth rate (SGR), feed conversion ratio (FCR), hematological parameters, lysozyme activity, respiratory burst activity, and overall immune responses in fish fed prebiotic-enriched diets compared to the control group. The combination diet containing Althaea officinalis and Hylocereus undatus extracts exhibited the highest growth performance and immune enhancement. Furthermore, challenge tests with Aeromonas hydrophila infection demonstrated significantly reduced post-challenge mortality and enhanced disease resistance in prebiotic-treated groups. The findings of the present study suggest that plant-derived prebiotics from A. officinalis and dragon fruit can serve as eco-friendly, sustainable, and effective alternatives to antibiotics in freshwater aquaculture nutrition and health management.