경북도내 강에서 채집된 담수어에 있어서 흡충류 피낭유충의 최근 감염상

Abstract

Recent pattern of infection rates and intensities with digenetic larval trematodes from fresh-water fishes was studied in the Cheongdo River, Hyungsan River and Kumho River, Kyongbuk Province during the period from March to November, 2008. Eleven species of digenetic larval trematodes from 3 families and 15 species of the fish and three undetermined species were found. The cyst of Cyathocotyle orientalis, Exorchis oviformis, and Metacercaria hasegawai were found most frequently in 11 species. Clonorchis sinensis was found in 10 species, and the infection rate was 82.6 percent in Gnathopogon atromaculatus’s flesh, 26.1 percent in fin and tail, and in Pseudorasbora parva, the infection rate of the flesh, fin and tail, or scales was each 50 percent. As far the intensities of Clonorchis sinensis, Gnathopogon atromaculatus was the most heavily infected species with an average number of 9.0 cysts per gram of flesh, and Zacco platypus was very lightly infected species with 0.03. In the Chungdo River, the cyst of Metacercaria hasegawai was found most frequently from 11 species out of 14 species of the fish, and Cobitis sinensis and Pseudogobio esocinus were the most highly infected with 75.0 percent, and the least infected by Zacco platypus with 8.3 percent. In the Hyungsan River, Exorchis oviformis was the most frequently found cyst from six species out of 10 species of the fish, and in the Kumho River, Exorchis oviformis was the most frequently found cyst from 2 species out of 6 species. These results indicate that the rate of infection with digenetic larval trematodes including Clonorchis sinensis was still relatively high, and the metacercarial burden in the fish varies greatly by different fishes in comparison with data reported previously in the same rivers.