Vol. 12, Special Issue 9 (2023)

Author(s):
Avishek Bardhan and H Shivananda Murthy

Abstract:
Aquaculture success hinges on managing stressors that impact aquatic organisms' welfare, health, growth and survival. While salt addition is known for stress reduction and antiseptic properties, it poses osmotic challenges for freshwater fish. Our study assessed salt exposure's impact on healthy monosex Oreochromis niloticus juveniles. A one-hour exposure to 10 and 30 g/L induced notable behavior, histology and erythro-morphological changes. Tissue histology revealed hyperplasia in epithelial and lamellar regions, with swelling, burst secondary lamellar tips, epithelial damage and pillar cell vacuolation. Epithelial hyperplasia seemed protective against excessive exosmosis. While behavior, gill histology and erythrocyte morphology showed recovery signs in 10 g/L, the short-term excessive 30 g/L osmotic shock could be fatally consequential. Prudent application of this method is crucial. However, careful consideration of concentration and duration is vital for aquatic organisms' well-being and survival. Further research should explore optimal salt exposure strategies and their long-term impact on fish health.