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The role of nematodes in transmission of parasitic protozoans to a new host
Choutková, Jana ; Bulantová, Jana (referee) ; Horák, Petr (advisor)
A question of transmission to new hosts is fundamental for all parasitic organisms. Some parasites are adjusted to transmit themselves to new hosts by direct way thanks to the resistant life stage, some others use one or more intermediate hosts. An extreme case is transfer by parasitization of another parasite from the same host. Use of another parasite as a transport vehicle helps to realize transmission and this phenomenon can be termed. One example is the protozoan Histomonas meleagridis. This protozoan lives in the intestine of galliform birds where it can attack the roundworm, Heterakis gallinarum, another parasite of the bird intestine. This protozoan, which does not produce any resistant cyst stage in its life cycle and migrates into the roundworm eggs. After release of the eggs to the external environment, the egg provides a protection against external factors and ensures transfer of the protozoan to the new host. Some data suggests that a similar mode of transmission to new hosts can also be used by some others protozoans. One of them is a protozoan from human intestine, Dientamoeba fragilis. Enterobius vermicularis, a pinworm which parasitizes the same host, could serve as a vector of this protozoan. Another potential example of this phenomenon could be Tritrichomonas muris from mouse in...
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