Morphometrics and seasonal occurrence of metacestodes of Neogryporhynchus cheilancristrotus (Cyclophyllidea: Dilepididae) in the blue bream (Abramis ballerus) from the Oder River (Germany/Poland).

From May 1993 to April 1995, the seasonal occurrence of metacestodes of Neogryporhynchus cheilancristrotus (Wedl, 1855) (Cyclophyllidea: Dilepididae) in its second intermediate host, the blue bream Abramis ballerus (L.) was studied monthly in the Oder River on the borders of Germany and Poland. Based on the parasite specimens found, detailed data on their morphometrics are presented. The metacestodes occurred in the blue bream intestine throughout the year (overall prevalence 27% and intensity 1-56 (mean 4.8) metacestodes per infected fish). Increased prevalences and mean intensities of infection were noted from March to June and November to December indicating that spring, late autumn and early winter are the main periods of new infections.