Uzorkovanje babuške (Carassius gibelio Bloch, 1782) provedeno je u Sakadaškom jezeru smještenom unutar Parka prirode Kopački rit. Od 111 ulovljenih babuški, kod devet je utvrđena prisutnost nametnika, trećeg ličinačkog stadija oblića Contracaecum sp. Prevalencija je iznosila 8 %. Ukupno je izolirano 3822 oblića, a intenzitet infekcije se kretao od 7 do 1078 oblića po ribi (u prosijeku 424,66 oblića po ribi). Brojnost i ukupna biomasa oblića pozitivno su korelirali s masom ribe (rs = 0,633333, p ˂ 0,05; rs = 0,666667, p ˂ 0,05). Fulton-ov faktor kondicije (CF) za babuške koje nisu imale nametnike iznosio je u prosjeku 2,275, dok je za babuške koje su bile inficirane oblićima iznosio 1,635. Iako je zabilježen niži kondicijski faktor kod inficiranih jedinki, nije utvrđena statistički značajna razlika u odnosu na neinficirane babuške.. A sampling of Prussian carps (Carassius gibelio Bloch, 1782) was conducted in Lake Sakadaš located within the Nature Park Kopački rit. Of 111 captured Prussian carps, 9 revealed the presence of a parasite, 3rd larvae stadium of roundworm Contracaecum sp. The prevalence was 8 %. A total of 3822 roundworms were isolated while infection intensity ranged from 7 to 1078 roundworms per fish (average of 424.66 roundworms per fish). Roundworm abundance and total biomass positively correlated with fish mass (rs = 0.633333, p ˂ 0.05; rs = 0,666667, p ˂ 0.05). The Fulton's condition factor (CF) for Prussian carps without parasites was on average 2.275, and for Prussian carps infected by roundworms 1.635. Although the recorded condition factor was lower for infected samples, no statistically significant difference was determined for uninfected Prussian carps.