parasites encystation in some crustacea and fish

The aim of the present study is to clarify the role of some crustacea and fish in transmitting some parasites to experimental hosts and discuss their zoonotic importance.This work was done to clarify the role of crustacea; fresh water crayfish (Procambarus clarkia), shrimps (Penaeus seliferus) and blue crabs (Callinectes sabidus) )and common sand smelt fish (Atherina sp.) in transmitting some parasites.A total of 900 shellfish; 400 fresh water crayfish, 300 white shrimps and 200 blue crabs were collected and examined for the presence of encysted metacercariae, cestode larvae, nematode larvae and protozoa cysts or oocysts.A total of 900 common sand smelt fish (Atherina sp.) were collected from Zagazig fish market during the period extended from December (2007) to May (2008).