In aquaculture, from seed production to commercial farming, fungal infections often occur even though we have applied many integrated disease prevention solutions as well as care and management of cultured subjects. In this technical bulletin, I would like to introduce a chemical Bronopol that can be said to be a chemical used specifically to treat fungal infections on aquatic animals that has been used well in the world such as Japan, UK, USA, Korea and Vietnam.
Various chemicals commonly used to kill fungal infections in fish have been studied extensively by a group of researchers (Willoughby and Roberts 1992; Kitancharoen et al., 1997; Duc, 2009; Oono and Hatai, 2007). In addition, hydrogen peroxide (H2O2) is a commonly used chemical in the prevention and treatment of fungal infections in fish eggs and commercial fish (Dawson et al., 1994; Kitancharoen et al., 1997). Sodium hypochlorite (NaClO) solution at a concentration of 200 ppm has the ability to inhibit fungi Fusarium (Khoa, 2005) and formol (HCHO) is used to prevent and treat fungal infections in salmon (Thorburn and Moccia, 1993). ). Recently, Bronopol (C3H6BrNO4) has been widely used in the prevention and treatment of fungal infections in salmon eggs (Pottinger and Day, 1999; Branson, 2002; Oono et al., 2007; Oono et al., 2008).
What is Bronopol?
Bronopol has the chemical formula (C3H6BrNO4). The chemical name of this substance is 2-Bromo-2Nitropropane-1,3-Diol. In the world, Bronopol is supplied to the market with trade names such as Pyceze, Onyxide 500. The world has allowed the use of Pyceze products with the main active ingredient, Bronopol, manufactured by Asia Animal Pharmaceutical CO.Ltd. (Achaupharm) to replace malachite green (prohibited product) in the treatment of ectoparasites.
The fungicidal effect of Bronopol
- Clean ponds, prevent fungi and microspore before culture time: 1 – 2 ml/ 1 m3of water, diluted with 10 – 15 ml of water and spread over pond surface in the morning before or after stocking 1 – 2 days.
- Treatment of fungi, microspore: 2- 3 ml/ 1 m3 of water, dilute with water and spread over the pond in the morning.
- Periodic use to prevent fungal infection: 1- 2 ml/ 1 – 1,5 m3, every 7 – 10 days in the morning.
- Prevention and treatment of fungal infections in the pond:
- For fingerlings: 1 ml/ 100 liters of water (repeat treatment after 48 hours) or 2 ml/ 100 liters of water for 2 hours/ day (water change or transfer to other tank after 2 hours).
- Fish eggs: 1 ml/ 100 liters of water, 30 minutes per day (from fertilized egg stage until eye points appear) to limit fungal infection, increase hatching rate.