Abstract
Summary The northern section of the Caspian Sea is an important fishery for Kazakhstan. In the present study, a total of 606 individuals of 13 fish species were collected. For each of Abramis brama , Alosa saposchnikowii , Atherina boyeri caspia , Carassius auratus , Clupeonella cultriventris , Cyprinus carpio , Liza aurata , Leuciscus aspius , Rutilus rutilus caspius , Sander lucioperca , Sander marinus , and Sander volgensis 50 individuals were examined whilst 6 individuals of Siluris glanis were examined. The nematode parasite Anisakis schupakovi was found in all fish species except Liza aurata, Carassius aurata , Cyprinus carpio and Rutilus rutilus at intensities ranging from 1 to 1197 parasites per infected fish. Trematodes of family Diplostomidae were also isolated from all fish except Alosa saposhnikowii, Clupeonella cultriventris and Sander marinus at intensities ranging from 1 to 242 parasites per infected fish. Other parasites found included the nematodes Porrocaecum reticulatum, Contracecum sp, Camallanus sp and Eustrongylus excisus; the cestodes Neogryporhynchus cheilancristrotus, Bothriocephalus opsariichthydis; the monogenean parasites Mazocraes alosa, Ancyrocephalus paradocus, Gyrodactylus spp, Ligophorus vanbenedenii and Dactylogyrus spp; and the crustacean parasites Ergasilus sp . and Synergasilus sp . In addition one unidentified species of nematode and a bivalve of the genus Unio was recovered from Rutilus rutilus caspius . There was no association between Fulton’s condition index and intensity of parasite infection.