Probiotic Efficacy in Aquaculture: The Role of Technospore® (Bacillus coagulans) in Improving Nile Tilapia (Oreochromis niloticus) Performance and Disease Resistance: a Study on Gut Health, Immunological Response, and Gene Expression

Abstract

This study evaluated the effects of Technospore® (Bacillus coagulans) supplementation on intestinal health, immune response, and Oreochromis niloticus (Nile tilapia) growth performance. The experiment divided fish into four groups: a control group fed an unsupplemented diet and three experimental groups receiving diets supplemented with 0.2 g/kg, 0.4 g/kg, and 0.8 g/kg of Technospore®, respectively. Results indicated that Technospore® supplementation significantly enhanced growth rates and feed efficiency in all treated groups, with the most pronounced improvements observed in the group receiving 0.4 g/kg. Furthermore, the study revealed that B. coagulans supplementation markedly boosted serum immune responses, as evidenced by increased phagocytic activity, phagocytic index, and lysozyme levels, following a challenge with Aeromonas hydrophila. Histological analysis showed improved gut morphology, while gene expression analysis indicated upregulation of immune-related genes, including liver IGF-1, GHR, HSP70, IL-1β, and TNF-α, as well as spleen TNF-α and IL-1β and intestinal C-lysozyme and TNF-α, both before and after the bacterial challenge. These findings suggest that dietary inclusion of Technospore® can significantly improve gut health and immune responses in tilapia, potentially serving as an effective prophylactic alternative to antibiotics in aquaculture.