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Jsou parmy obecné v době výtěru "jedovaté" pro ostatní vodní organismy?
ŠVEJDA, Pavel
This bachelor thesis deals with fish toxicity with the emphasis on the barbel (Barbus barbus Linnaeus, 1758). Its tissues and especially roe cause poisoning to human known as a "barbel cholera". Possible lethal effects of barbel the killer shrimp Dikerogammarus villosus (Sowinsky, 1894), the marbled crayfish Procambarus virginalis Lyko, 2017 and the round goby Neogobius melanostomus (Pallas, 1814) were examined in this thesis. Different types of tissues and early life stages of barbel were used due to the indistinct distribution of possible toxin in fish body. In addition, using a behavior test, where marbled crayfish were used as an experimental organism, we monitored possibilities of toxin detection by consumer. Our results suggest that there is no evidence of barbel lethal toxicity on chosen consumers. We also did not find evidence that crayfish are able to recognize flesh of ready and unready to reproduce barbel. To sum up, we did not find evidence that toxin which is present in barbel body affect given consumers. It can be given either their co-evolution (arms race) or their ancestors had never been susceptible on this toxin. Thus, there can only be a spontaneous effect of mentioned toxin on mammals or humans.
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