Objective: The prophylactic and antioxidative role of the dried powdered of Ocimum sanctum (Tulasi) was measured in Hexamita-infected fish Anabas testudineus.
Method: Four groups of infected fish were kept in four separate aquariums and the following doses of leaf powder applied (25 mg, 50 mg, and 100 mg/L) for 10 days, and the first group is considered as control and no such treatment is given there.
Results: Histopathology showed a remarkable alteration in the structure of liver tissue. Progressive changes observe along with the treatment schedule in hepatic histology and differential count of blood. Results showed that Hexamita infections significantly increased (p<0.05) the oxidative stress in the liver of infected fish. Whereas the treated fish exposed to different doses of powdered leaf of O. sanctum show significantly higher levels of antioxidant enzymes (Catalase, Superoxide dismutase, Glutathione peroxidase) and lower levels of stress marker (Malondialdehyde) than control fish. This treatment caused a rapid skin formation in the scar region. The highest recovery found in 100 mg/L doses of leaf powder, whereas the least recovery found in 25 mg/L group.
Conclusion: The findings of the present study may play a key role in aquaculture industry for controlling the death of fish from Hexamita infection.