Occurrence and elimination of Neoheterobothrium infection from cultured oliver flounder (Paralichthys olivaceus) in the western coast of Korea

Jang, Hwan; Moon, Jin-San; Kim, Ji-Yeon; Joh, Seong-Joon; Son, Seong-Wan

Korean Journal of Veterinary Research 2007;47(3):299-302.

Hwan Jang, Jin-San Moon, Ji-Yeon Kim, Seong-Joon Joh, Seong-Wan Son

National Veterinary Research and Quarantine Service, MAF

서해안 양식 넙치에서 Neoheterobothrium 감염증의 발생 및 치료

장환, 문진산, 김지연, 조성준, 손성완

국립수의과학검역원

Abstract

Neoheterobothrium hirame (N. hirame) is a large blood-feed gill-worm infecting the highly prized olive flounder. The present study was reported the occurrence and elimination of Neoheterobothrium infection from young cultured oliver flounder in the western coast of Korea. Flounder (weight 18-25 g, length 10-15 cm) were obtained from a cultured farm at Taean of Korea at May 2006. A lot of flounder died with serious anemia. We isolated N. hirame from the buccal cavity wall of dead flounder. Adult parasites were 5-15 mm in total length, with 4 pairs of clamps on the pedunculated haptor and isthmus region embedded in host tissue, while immature and sub-adults were identified the attachment to the gill filaments, rakers and arches with the clamps. All fish with infection were treated with 8% NaCl-supplemented seawater for 1 and 10 min at $22^{circ}C$, respectively. The significant reduction in mortality (6.7%) was observed among fish treated with 8% salt water for 10 minutes, when compared with that of non-treatment group (100%).

Key Words: olive flounder, paralichthys olivaceus, neoheterobothrium hirame