The anaesthetic effects of sodium bicarbonate (baking soda) on greenhead tilapia (Oreochromis macrochir, Boulenger 1912) broodstock

Abstract

The use of anaesthetics to lower stress in fish farming activities and other routine operations is common in aquaculture. Sodium bicarbonate, also known as baking soda/powder is a recognised and accepted anaesthetic substance commonly used in aquaculture. However, this is not the case in some developing countries such as Zambia, thus limiting the fish farmers’ options of using cheaper locally available chemicals as anaesthetic agents in fish culture. Our study aimed at assessing the anaesthetic effects of sodium bicarbonate on greenhead tilapia broodstock. A total of 90 Oreochromis macrochir broodstock (weight 160 ± 10 g and length 169 ± 10 mm) were exposed in triplicates to a sodium bicarbonate bath solution at concentrations of 0.0, 5.0, 10.0, 15.0, 20.0 and 30.0 g/L; and fish per transparent plastic tank (20 L) were used. Induction and recovery time were monitored using a stopwatch. The results of this study revealed a significant effect (P < 0.001) of sodium bicarbonate on both the induction and recovery time for O. macrochir broodstock. Survival rate was 100% and fish resumed normal swimming and feeding soon after the experiment. We therefore recommend sodium bicarbonate to be used as an anaesthetic owing to its availability and affordability.

Keywords

• Sodium bicarbonate
• Anaesthetic dosage
• Anesthetic efficacy
• Induction time
• Recovery time
• Oreochromis macrochir