The efficacy of Virkon-S for the control of saprolegniasis in common carp, Cyprinus carpio L

Abstract

Background Saprolegnia parasitica is a fish pathogen that causes severe economic losses worldwide. Virkon-S is a well-known disinfectant known to exhibit antimicrobial activities against bacteria, viruses, and fungi. In this study, we tested the anti-fungal activity of Virkon-S against S. parasitica, the major causal agent of saprolegniasis.MethodsThe lowest concentration of Virkon-S that prevented germination or the visible growth of spores and the percent spore germination were determined using potato dextrose agar plates containing different concentrations of Virkon-S. The cytotoxic effect was evaluated using the Ez-Cytox Cell Viability Assay with epithelioma papulosum cyprini (EPC) cells grown in L-15 medium and acute toxicity tests were carried out with cultured fingerlings of common carp for 96 h. Artificial infection with S. parasitica was performed by placing the fish in tanks containing zoospores of S. parasitica after descaling and wounding at three positions. The diseased fish were kept in tanks containing 2, 4, and 10 ppm of Virkon-S for 10 days to observe the treatment effect.ResultsThe in vitro assay results showed that Virkon-S could inhibit spore germination and the resulting mycelial growth at a concentration as low as 4 ppm. No cytotoxic effect on EPC cells was observed even at a concentration as high as 100 ppm. Additionally, no acute toxicity in the common carp was observed at 10 ppm following 96 h exposure. Ten days of treatment with 4 and 10 ppm Virkon-S resulted in complete reversal of artificially-induced saprolegniasis in the common carp.DiscussionThis data indicates that Virkon-S can be used for the control of saprolegniasis without harmful effects in fish. However, further research on the effect in humans and food supplies is necessary.

Saprolegniosis in Amphibians: An Integrated Overview of a Fluffy Killer Disease

“…Due to its efficacy against pathogenic bacteria, viruses, and fungi and its relative safety regarding animal and human health, Virkon-S has been authorized by the United Nation’s Food and Agriculture Organization and approved in Korea to secure biosafety and strengthen Emergency Disease Control Contingency Planning. Presently, Virkon S is being tested as a potential treatment agent in a new approach to combat skin disease in fish [ 122 ]. It is effective in inhibiting spore release by S. parasitica and impairs mycelial growth at concentrations above 4 mg/L.…”

“…The results showed no mortality in the fingerlings at concentrations below 10 mg/L after a 96 h exposure period, and treatments of 4 and 10 mg/L proved to be effective in the complete reversal of artificially induced saprolegniosis in the common carp. Moreover, no cytotoxic effect on epithelioma papulosum cyprini (EPC) cells was observed even at a concentration as high as 100 mg/L [ 122 ]. Regarding amphibians, Virkon S has been used to prevent the spread of B. dendrobatidis among wild and laboratorial populations and to sterilize boots and any field material; it has even been used during housekeeping procedures.…”

Efficiency of Syzygium aromaticum and Punica granatum extracts for the prevention of saprolegniasis on Oreochromis niloticus fish

“…The use of chemical fungicides such as formalin, hydrogen peroxide, copper oxysulphate and malachite green in controlling saprolegniasis was widely used as therapeutic agents in aquaculture all over the world. (Barnes et al, 2003; Rahman & Choi, 2018). However, due to the teratogenic and carcinogenic potential of malachite green (Hussain Bhat et al, 2020), its use was banned in the USA in 1991 (Ali et al, 2014), in Italy in 1994, and in China in 2002 (Hu et al, 2013).…”

“…The use of chemical fungicides such as formalin, hydrogen peroxide, copper oxysulphate and malachite green in controlling saprolegniasis was widely used as therapeutic agents in aquaculture all over the world. (Barnes et al, 2003;Rahman & Choi, 2018). However, due to the teratogenic and…”

Histopathological Changes of Common Carp (Cyprinous carpio) Vital Organs Exposed to Virkon at Different Periods

“…In 1986, Antec International (Antec International Limited, Sudbury, Suffolk, UK) introduced Virkon-S as a tool for agriculture and animal production. It is thought to be one of the most innovative farm disinfectants [3].…”