The early half of the last century has witnessed
a great attention to family Heterophyidae especially in Middle
and Far East since infecting both man and animals. Seasonal
variation concerning prevalence and intensity of fish infection.
Fish specimens were collected from highly endemic region in
Alexandria governorate during summer and spring seasons.
Encysted metacercariae were identified and used in
subsequent experimental infection of laboratory mice was
carried out to allow morphological identification of eggs and
adult worms. The prevalence of infection was much higher in
summer (90.10%) than in spring season (54.76%).P.genata
has proved highly infective, since all experimental mice had
acquired infection. Morphological characteristics may help
distinguish P.genata stages from other heterophyids