: A study of infestation patterns for larval trematodes from fresh-water fish and brackish-water fish was carried out during the period from June to October in 1982. They were collected by netting, fishing with rod and line, and using the bait of crushed oil cake in a transparent plastic bowls at the three localities, Daebon-dong, Kugil-dong, and Hoam-dong in the river Taechong, Kyungpook Province, Korea. Five species of fresh-water fish, the crussian carp, Carassius carassius Linnaeus, the bullhead, Coreobagrus brevicorpus Mori, the fat minnow, Moroco oxycephalus (Bleeker), the flat bitterling, Paracheilognathus rhombea(Temminck et Schlegel), and the catfish, Parasilurus asotus (Linnaeus), and two kinds of brackish-water fish, the grey mullet, Mugil cephalus (Linnaeus) and the sweetfish, Plecoglossus altivelis (Temminck et Schlegel) were examined. Four species of the metacercariae, Exorchis oviformis, Metacercari hasegawai, Metorchis orientalis and undetermined larvae were found. Of these, the encysted larvae of the human intestinal fluke, Metagonimus yokogawai, were found from three kinds of fresh-water fish, the crussian carp, the bullhead and the fat minnow and one species of brackish-water fish, the sweetfish and the infestation rates for the larvae varied appreciably from fish to fish. The intensity of infestation with the Metagonimus larvae in the three species of fresh-water fish as low, and the average number of the larvae per gram of flesh varied from 0.5 to 0.2. By comparison, the brackish-water fish was more heavily infested and the mean number of cysts per gram of flesh in Plecoglossus altivelis was 109.2. It was found that infection with Metagonimus yokogawai is caused by consuming raw fresh-water fish and brackish-water fish caught in the river Taechong, Kyungpook Province, Korea.
parasitology-helminth-trematoda ; Metagonimus yokogawai ; Carassius carassius ; Coreobagrus brevicorpus ; Moroco oxycephalus ; Paracheilognathus rhombea ; Parasilurus asotus ; Mugil cephalus ; Plecoglossus altivelis ; epidemiology ; metacercaria

The present work which was investigated in July 1979, was to observe the wormicidal effects of the external mucous substances of 9 species of fresh water fishes (Cyprinus carpio, Parasilurus asotus, Anguilla japonica, Ophicephalus argus, Carassius carassius; golden crusian carp, Misgurnus anguillicaudatus, Zacco platypus, Pseudorasbora parva and Carassius carassius; crusian carp) on cercaria, liberated metacercaria and adult of Clonorchis sinensis. The mucous substances extracted by ether from the above 9 species of fishes were separated into many spots on the silica gel thin layer chromatography, and divided into many fractions in the silica gel column chromatography which used petroleum ether (30 percent) and chloroform (70 percent) as a solvent. On the silica gel thin layer chromatography of ether extracts from 9 species of fresh water fishes, each of the Rf. values which had wormicidal effect on the cercaria of C. sinensis were different from others; Rf. value of C. carassius (crusian carp) was 0.937, 0.709 in O. argus, 0.612 in A. japonica, 0.576 in P. asotus, 0.451 in C. carpio, 0.701 in Z. platypus, 0.385 in C. carassius(golden crusian carp) and 0.15 in P. parva. Time for wormicide was different from each other, too. It took 14 min. in a case of C. carassius(crusian carp), 25 min. in Z. platypus, 26 min. in C. carassius(golden crusian carp), 28 min. in C. carpio, 30 min. in P. asotus, 35 min. in O. argus, 40 min. P. parva and 180 min. in A. japonica. But any of the spots of M. anguillicaudatus did not show wormicidal effect on the cercaria within 10 hours. In the silica gel column chromatography of ether extracts from 9 species of fresh water fishes, the fractions which had wormicidal effect on the metacercaria of C. sienesis were different from each other; in a case of C. carassius(crusian carp), the first fraction only had wormicidal effect, the 2nd in P. asotus, the 3rd in O. argus, the 4th in C. carassius(golden crusian carp), the 2nd in C. carpio and the 4th in P. parva. Time for wormicide was 40 min. in C. carassius(crusian carp), 52 min. in P. asotus, 74 min. in C. carassius(golden crusian carp), 92 min. in O. argus, 95 min. in C. carpio and 140 min. in P. parva, but any of the fractions of A. japonicas, M. anguillicaudatus and Z. platypus did not show wormicidal effect within 10 hours. The fractions which had wormicidal effect on the metacercaria of C. sinensis had also the same effect on the adult, but it took longer time to kill them. It took 3 hours in a case of C. carassius(crusian carp), 4 hrs. in C. carassius(golden crusian carp), 5 hrs. in P. asotus, 6 hrs. and 6 min. in O. argus, 6 hrs. and 10 min. in C. carpio and half and 6 hrs. in P. parva. But any of the fractions of A. japonica, M. anguillicaudatus and Z. platypus did not show wormicidal effect within 24 hrs.
parasitology-helminth-trematoda ; Clonorchis sinensis ; mucous substance ; Cyprinus carpio ; Parasilurus asotus ; Anguilla japonica ; Ophicephalus argus ; Carassius carassius ; Misgurnus anguillicaudatus ; Zacco platypus ; Pseudorasbora parva

This study was undertaken to elucidate the status of Metagonimus species infection and to demonstrate the first and the second intermediate hosts of the fluke at the several localities along the Gum river, Chungchung-nam Do, Korea from March 1979 to October 1980. The results are summarized as follows: Total 790 stool specimens of inhabitants from 6 localities along Gum river were examined by the combination of cellophane thick smear technique and formalin-ether concentration technique. The positive rate of intestinal helminths was 80.3 percent, and the egg positive rate of Metagonimus sp. was 21 percent from a total of 790 specimens examined. In the age bracket of 20-49, the positive rates of Metagonimus sp. were 31.1-36.5 percent, and the males (26.8 percent) were infected three times higher than females (8.9 percent). By the area of the river, Gumsan which is located upper stream showed the highest positive rate (40.5 percent) of the fluke, whereas the rates decreased gradually toward upper part of river (Muju) or the descending lower area of the river. The most lower area of river (Gangkyeong and Nonsan), no positive Metagonimus infection case was found. The infection rate of Clonorchis sinensis in 790 was 37.3 percent, and the status of mixed infection of Metagonimus with C. sinensis was found 127 cases (76 percent) out of 166 cases with Metagonimus infection. The result of measurement of ova from 166 cases of Metagonimus infection, large ova were found in 41.1 percent, small size ova in 31.9 percent and the mixed type in 27.1 percent, respectively. The adult worms were recovered from the 6 cases after treatment with niclosamide, and the measurements of the worms showed similar morphological characteristics of the Metagonimus yokogawai. Twenty-two species in 5 families of fresh water fish were caught. Out of 22 species of fish, 18 species were found infected with metacercaria of Metagonimus. In order to observe the distribution of metacercariae in the body and the rate of infection of the individual host, a total of 94 Pseudogobio esocinus were examined. Total 84 (89.4 percent) out of 94 fish were infected with the metacercariae and the rates of distribution of the metacercaria were observed in the following order: on scale; 93.4 percent, in gill; 3.2 percent, head part; 2.9 percent, but a few metacercaria was found in muscle and visceral organs. The development of the metacercariae which were isolated from the scale of Pseudogobio esocinus were experimentally traced in the albino rat host from one day to 30 days after infection. At the 6th day, several eggs were visible in the uterine tubule of the some worms, on the 10th day, worms became 326.0 x 208.0 micrometer in size, however the bodies of worms grew no more until the 30th day after infection. The oral sucker was larger in size than the ventral sucker during early stage of the worms, but the 7th day after infection, it reversed. The ventral sucker situated on the ventral right side of the body. Right side of testis laid somewhat toward, and uterus and vetellaria extended to the posterior margin of the right testis. Snails(Koreanomelania nodifila var. ovulum) were collected in the river, Buri-Myeon, Gumsan-Gun, and found the natural emerging ophthalmo-pleurophocercus cercaria. From the above result, the prevalence of Metagonimus species infection showed relatively higher rates from the inhabitants along the middle to upper localities of the river. Even though no sweetfish was caught in the surveyed areas, Gum river basin is the one of the new endemic foci of metagonimiasis in Korea.
parasitology-helminth-trematoda ; Metagonimus spp. ; metagonimiasis-epidemiology ; taxonomy ; Ascaris lumbricoides ; Trichuris trichiura ; hookworm ; Trichostrongylus orientalis ; Clonorchis sinensis ; Taenia sp. ; Pseudogobio esocinus ; Acheilognathus intermedia ; Carassius carassius ; Hemibarbus labeo ; Hemibarbus longirostris ; Paracheilognathus rhombea ; Parapelecus jouyi ; Pseudopungtungia nigra ; Pungtungia herzi ; Sarcocheilichthys wakiyae ; Zacco playtpus ; Zacco temmincki ; Gobiobotia brevibarba ; Gobiobotia macrocephalus ; Siniperca kawamebari ; Siniperca scherzeri ; Liobagrus andersonii ; Pelteobargrus fluvidraco ; Pseudobagrus emarginatus ; Pseudobagrus sp. ; Mogurnda obscura ; Parasilurus asotus

In order to know relationship between the clavate cells of epidermis and infectivity of metacercariae of C. sinensis. histological investigation of epidermis was carried out on the 26 species of fresh-water fish collected from the main rivers in Korea. Results were summarized as it follows: In general clavate cell had a single nucleus at its center. However it was observed in Liobagrus mediadiposalis and Pelteobagrus fuluidraco that clavate cell had two nuclei with and independent so-called light halo of Oxner and in some cases had none of them. In following species; Misgurnus anguillicaudatus, Cobitis taenia, Liobagrus mediadiposalis, Pelteobagrus fuluidraco, Parasilurus asotus and Anguilla japonica, scales were not detected or buried in the dermis layer, and the epidermis was mostly consisted of clavate cells. Among these species, it was observed that no metacercariae were found. In case of Cyprinus carpio, Carassius carassius (crusian carp and golden crusian carp), Sarcocheilichthys czerskii, Pungtungia herzi and Coreoleuciscus splendius, scales were exposed over the epidermis, in which clavate cells were abundantly found. In these species, a few of the metacercariae were detected. On the other hand, no clavate cells were observed in Pseudorasbora parva , Zacco platypus, Microphysogobio koreensis, Gnathopogon majimae, Gnathopogon coreanus, Acheilognathus signifer, Acheilognathus yamatsutae, Cultriculus eigenmanni, Coreoperca herzi, Pseudoperilampus uyekii, Pseudoperilampus notatus and Pseudogobio esocinus. These fishes with exposed scales on the epidermis were well known to serve as the second intermediate hosts of C. sinensis. From the above results obtained, it was suggested that the existance of clavate cells in the epidermis of the fresh-water fish seems to be correlated with the infectivity of the metacercariae of C. sinensis.
parasitology-helminth-trematoda-Clonorchis sinensis ; host ; Liobagrus mediadiposalis ; Pelteobagrus fuluidraco ; Misgurnus anguillicaudatus ; Cobitis taenia ; Liobagrus mediadiposalis ; Pelteobagrus fuluidraco ; Parasilurus asotus ; Anguilla japonica ; Cyprinus carpio ; Carassius carassius ; Sarcocheilichthys czerskii ; Pungtungia herzi ; Coreoleuciscus splendius ; Pseudorasbora parva ; Zacco platypus ; Microphysogobio koreensis ; Gnathopogon majimae ; Gnathopogon coreanus ; Acheilognathus signifer ; Acheilognathus yamatsutae, Cultriculus eigenmanni ; Coreoperca herzi ; Pseudoperilampus uyekii ; Pseudoperilampus notatus ; Pseudogobio esocinu