The association of eustrongylidosis with other types of parasitic invasions of the predatory fishes in the natural waters of Southern Ukraine

The article presents the result of the research of predatory fishes — sander (Sander lucioperca Linnaeus, 1758), perch (Perca fluviatilis Linnaeus, 1758) and pike (Esox lucius Linnaeus, 1758) in the waters of the Dnipro-Buh estuary and in the delta of the Dnipro river. The possible associations of eustrongylidosis with other types of parasitic invasions of fishes have been established. It has been revealed up that the researched fish has been invaded mostly by such agents of parasitic diseases as digenetic trematodes and nematodes — 35.6 % and 31.8 % respectively. The least common group of parasites affecting commercial fishes was acanthocephalides — 0.71 %. The invasion of perches by the diplostomosis agents was noticed. The invasion extensiveness (IE) counted 50.7 %, and the invasion intensiveness (II) counted 2–41 samples. Other parasitic diseases affecting perches were paracoenogonymonosis (ІE — 15.3 %, ІІ — 7–31 samples); post diplostomosis (ІE — 9.97 %, ІІ — 87–118 metacecaria); dactylogyrosis (ІE — 37.2 %, ІІ — 5–14 samples); lavral trienophorosis (ІE — 1.66 %, ІІ — 2–5 cysts); eustrongylidosis (ІE ІІ — 1–3 samples);argulosis (ІE — 12 %, ІІ — 6–18 samples); ergazylosis (ЕІ — 6.02 %, ІІ — 11–26 maxillopods); The parasitic fauna of pikes is characterized by the agents of diplopstomosis (ІE — 62 %, ІІ — 3–17 larvae); paracoegonimosis (ІE — 42.7 %, ІІ — 1–38 metacecaria); postodiplostomosis (ІE — 10.7 %, ІІ — 23–51 sam-ples); dactylogyrosis (ІE — 17.8 %, ІІ — 2–15 samples); diplozoonosis (ІE — 0.67 %, ІІ — 1 sample); trienophorosis (ІE — 56.5 %, ІІ — 1–9 samples); valiporosis (ІE — 24.9 %, ІІ — 1–11 plerocercoids); eustrongylidosis (ІE — 58.9 %, ІІ — 1–13 larvae); rafidoscarosis (ІE — 76.4 %, ІІ — 8–31 nematodes); pseudoekhinorinchosis (ІE — 2.02 %, ІІ — 2–9 acanthocephala); argulosis (ІE — 28.2 %, ІІ — 2–63 parasites). The parasitic invasions of slander were also registered: for example, with diplopstomosis (ІE — 52.7 %, ІІ — 1–13 parasites); paracoenogonymonosis (ІE — 15.3 %, ІІ — 1–17 metacecaria); postodiplostomosis (ІE — 8.8 %, ІІ — 5–84 larvae); dactylogyrosis (ІE — 31 %, ІІ — 2–23 samples); valiporosis (ІE — 5.9 %, ІІ — 1–2 plerocercoids); eustrongylidosis (ІE — 58.1 %, ІІ — 1–9 samples); rafidoscarosis (ІE — 18.2 %, ІІ — 5–8 nematodes); pseudo-ekhinorinchosis (ІE — 0.49 %, ІІ — 2 acanthocephala); ergazylosis (IE — 47.2 %, ІІ — 7–28 maxillopods).