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Fish Herpesviruses
Čečetka, Petr ; Forstová, Jitka (advisor) ; Kuthan, Martin (referee)
Herpetic viruses that attack fish are ones of the most widespread virus pathogens, threatening modern day fish population not only in the wild but also those that are farmed. There are many types of the pathogen, from the ones those do not cause severe diseases to those that are extremly dangerous, spread without any control and caused vast losses in commercial farming and in wild populations. Most of the viruses exhibit increased sensitivity on heat and stress factors, which are the most common reasons of the repeating outbreak of disease. To the best described fis herpesvirus viruses attacking fresh water fishes belong. Nowadays more and more herpetic viruses which attack mainly salt water fis are beeing discovered. Powered by TCPDF (www.tcpdf.org)
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Fish Herpesviruses
Čečetka, Petr ; Forstová, Jitka (advisor) ; Kuthan, Martin (referee)
Herpetic viruses that attack fish are ones of the most widespread virus pathogens, threatening modern day fish population not only in the wild but also those that are farmed. There are many types of the pathogen, from the ones those do not cause severe diseases to those that are extremly dangerous, spread without any control and caused vast losses in commercial farming and in wild populations. Most of the viruses exhibit increased sensitivity on heat and stress factors, which are the most common reasons of the repeating outbreak of disease. To the best described fis herpesvirus viruses attacking fresh water fishes belong. Nowadays more and more herpetic viruses which attack mainly salt water fis are beeing discovered. Powered by TCPDF (www.tcpdf.org)
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Use of peracetic acid in pond aquaculture
FRANĚK, Roman
The aim of the thesis was to verify use of peracetic acid (PAA) in production conditions for ectoparasites control in carp pond farming. First test was about evaluation of organic load in pond water on speed PAA decay in two temperature regime (11 15 and 21 °C). Results showed that between 3 6 hours from PAA application the concentration of PAA was under a half of the initial concentration (6 mg.l-1). Also statically important differences (p= < 0.05) were found in speed of decay between samples with organic load (3 samples from ponds) and samples without organic load (distilled and tap water) in both temperature regimes. Application of PAA during the transport of fish into the transport boxes was performed in three age categories (1, 2 and 3 years old common carps), where the fish were exposed for 60 90 minutes in 1.5 mg.l-1 PAA as Persteril 36. Parasitic examinations of skin and gills showed reduction of number protozoal parasites (Trichodina spp. and Apiosoma spp.) in individuals comparing with control. Against other detected parasites was PAA ineffective. Statistical evaluation showed significant (p= <0.05) decrease in prevalence only in 3 cases out of 19 in total. Long-term four days long fish bath of carps which were heavily infested by Saprolegnia parasitica in 1.5 mg.l-1 PAA an positive effect on the overall survival was found. In the control group mortality reached 100 % the third day of trial, in contrast with treated group where was Saprolegnia parasitica succesfuly eliminated and overall moratily was 40 %. Continual fourteen days long application of PAA by peristaltic pump did not proved.
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