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Morphological and functional variability of secretory glands in cercariae of chosen trematode groups
Krčmářová, Veronika ; Bulantová, Jana (advisor) ; Mikeš, Libor (referee)
Trematodes are characterized by their complex life cycles that include definitive hosts and variable number of intermediate hosts. Transfer of the parasite from the first intermediate host to the other is usually realized by larval stage called cercaria. After finishing of their development within the first intermediate host, morphology and fate of these larval stages vary according to the way of infection of the next host. Some cercariae actively penetrate directly to their definitive hosts trough their body surface, other encystate in the outer environment where they wait in a form of metacercariae to be ingested by definitive host. Both of these ways can be combinated and cercariae encystate inside second intermediate host after they actively penetrate them. Exceptionally, cercariae do not leave the sporocyst in which they were developing inside the first intermediate host. They encyst there waiting for ingestion by the definitive host. Various types of secretory glands have been developed in cercariae for successful direct infection of next hosts, survival of parasite in adverse conditions of outer environment or for transformation of one larval stage to subsequent one. Variability in morphology and function of these secretory glands in cercariae is closely connected with differences in life...
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Morphological and functional variability of secretory glands in cercariae of chosen trematode groups
Krčmářová, Veronika ; Bulantová, Jana (advisor) ; Mikeš, Libor (referee)
Trematodes are characterized by their complex life cycles that include definitive hosts and variable number of intermediate hosts. Transfer of the parasite from the first intermediate host to the other is usually realized by larval stage called cercaria. After finishing of their development within the first intermediate host, morphology and fate of these larval stages vary according to the way of infection of the next host. Some cercariae actively penetrate directly to their definitive hosts trough their body surface, other encystate in the outer environment where they wait in a form of metacercariae to be ingested by definitive host. Both of these ways can be combinated and cercariae encystate inside second intermediate host after they actively penetrate them. Exceptionally, cercariae do not leave the sporocyst in which they were developing inside the first intermediate host. They encyst there waiting for ingestion by the definitive host. Various types of secretory glands have been developed in cercariae for successful direct infection of next hosts, survival of parasite in adverse conditions of outer environment or for transformation of one larval stage to subsequent one. Variability in morphology and function of these secretory glands in cercariae is closely connected with differences in life...
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Testing of the efficiency of selected antiparasitics on the metacercaria of the eye flukes (Diplostomum spathaceum) in grass carp (Ctenopharyngodon idella).
IPSEROVÁ, Jarmila
In this thesis, the efficiency of orally applied praziquantel (PQ) in two concentrations (Pramik 1 and Pramik 2) and mebendazole (MB) were tested on metacercaria of eye flukes (Diplostomum spathaceum, Rudolphi, 1819) in the grass carp (Ctenopharyngodon idella, Valenciennes, 1844). Naturally infected fish (average fish weight was 1.6 g and standard deviation was 0.1) were divided into four groups, for each tested group (Pramik 1, Pramik 2 and MB) belonged two aquariums of 100 liters each with 25 fish and for a control group belonged three aquariums of 100 liters each with 25 fish. The fish in the individual groups were fed with medicated feed containing praziquantel (Pramik 1 - 2.5 g PQ. kg-1 of feed, Pramik 2 - 1.25 g PQ. kg-1 of feed) and medicated feed mixture KP1 enriched with mebendazole (2.5 g MB. kg-1 of feed). The control group was fed with KP1 without drug addition. During the test the parasitological examinations of the ophthalmic lens were performed. The prevalence and intensity of infection were recorded. In the group of fish fed with medicated mixture containing MB, no statistically significant differences of the intensity of the infection indicating the MB potential in the fight against this fish infection were reported during the test. In the case of tested groups of fish fed with medicated feed mixture containing PQ (Pramik 1, Pramik 2), a statistically significant difference in the intensity of the infection was proved compared with the control group already after the first examination (estimated dose of consumed PQ. kg-1 of weight of fish = 500 and 250 mg). Near complete elimination of the eye flukes occurred in the group fed with feed mixture Pramik 1 after the expected consumption of 900 mg PQ. kg-1 of weight of fish. Statistically significant differences in the intensity of the infection in PQ treated fish groups compared to control groups indicate the usability of medicated feed containing PQ in the fight against fish diplostomosis.
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