Seasonal distribution and ecology of some Dactylogyrus species infecting Alburnus alburnus and Carassius carassius (Osteichthyes: Cyprinidae) from Porsuk River, Turkey

Abstract

In this research, gill parasites of two Cyprinid fish (Alburnus alburnus and Carassius carassius) from the upper basin of Porsuk river were studied. Fish samples were obtained monthly at intervals during 2003 to 2004. The intensity of infection was investigated depending on the parasite species, the years and seasons, and host fish species. Four Dactylogyrus species were identified in the gills of host fishes Dactylogyrus fraternus (Wegener, 1909), Dactylogyrus alatus (Linstow, 1878) and Dactylogyrus minutus (Kulwiec, 1927) on A. alburnus and D. minutus and Dactylogyrus anchoratus (Dujardin, 1845) on C. carassius. The prevalence, abundance and mean intensity of Dactylogyrus infection for each parasite species was determined as follow: D. fraternus (49.6%, 2.58 and 5.20), D. alatus (28.1%, 0.61 and 2.18) and D. minutus (35.1%, 1.61 and 4.61) in A. alburnus and D. minutus (40.5%, 1.00 and 2.49), D. anchoratus (37.6%, 0.38 and 4.63) in C. carassius. The highest intensity was recorded for D. fraternus while the lowest was recorded in D. alatus. However, no marked difference was recorded among the parasite species.

Key words: Alburnus alburnus, Carassius carassius, Dactylogyrus fraternus, Dactylogyrus alatus, Dactylogyrus minutus, Dactylogyrus anchoratus, seasonal distribution.