Title Page
Contents
Abstract 8
I. Introduction 10
II. Materials and methods 13
2.1. Saprolegnia parasitica cultures 13
2.2. Fish and rearing conditions 13
2.3. Virkon-S 14
2.4. Determination of minimum inhibitory concentration (MIC) 14
2.5. Mycelia growth inhibition on PDA plates 15
2.6. Inhibition of spore germination 16
2.7. Cytotoxicity of Virkon-S on Epithelioma Papulosum Cyprini (EPC) cell 17
2.8. Acute toxicity against common carp 18
2.9. Inhibition of fungal infection by Virkon-S in tank 19
Experimental infection of fish 19
Confirmation of infection by S. parasitica 20
Treatment of Saprolegniasis with Virkon-S 20
III. Results 21
3.1. Determination of minimum inhibitory concentration (MIC) 21
3.2. Mycelia growth inhibition test 23
3.3. Inhibition of spore germination on PDA plates 25
3.4. Enumeration of the inhibition of spore germination 27
3.5. Cytotoxicity of Virkon-S on cultured EPC cells 29
3.6. Acute toxicity test of Virkon-S on common carp 31
3.7. Induction of artificial infection and treatment with Virkon-S 34
IV. Discussion 38
V. Conclusion 41
VII. References 43
Table 1. Cumulative mortality of common carp during acute exposure to Virkon-S 32
Table 2. Healing of artificially induced saprolegniasis by Virkon-S treatment 37
Figure 1. Spore germination and mycelial growth of S. parasitica in the presence of... 22
Figure 2. Inhibition of S. parasitica mycelia growth on PDA containing different... 24
Figure 3. Inhibition of zoospore germination and the resulting mycelial growth on PDA... 26
Figure 4. Inhibition of zoospore germination and on PDA plates by different... 28
Figure 5. Cytotoxic effect of Virkon-S on cultured Epithelioma Papulosum Cyprini (EPC)... 30
Figure 6. Common carp in the progress of acute toxicity test. Picture was taken... 33
Figure 7. Clinical signs of S. parasitica in on fish body that had been artificially... 35
Figure 8. Common carp recovered from saprolegniasis by treatment with Virkon-... 36