• Korean journal of applied entomology
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• v.56 no.1
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• pp.29-39
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• 2017

To compare the features of ground-dwelling invertebrates according agroecosystems, we selected paddy fields, dry fields, orchards in the Eastern region of Korea. The surveys were performed by using pit-fall traps twice per year from 2013 to 2015. Total 6,420 individuals of 172 species belonging to 13 orders, 58 families were investigated in the Eastern region, the species of Hymenoptera (38.26%), Orthoptera (16.28%) accounted large portion of the communities. In the geographical observation, invertebrates were caught was 2,983 individuals in Gyeongsangnam-do, the diversity index of Gyeongsangbuk-do community was higher than of the others and abundance and species richness of paddy field were higher than from dry field or orchard. To understand the relation between taxonomic groups and environmental factors, we carried out the canonical correspondence analysis and hierarchical clustering. As a result, Homoptera, Blattaria, Isoptera, and Coleoptera were positively related to soil pH, soil temperature, and moisture contents, and negatively related to the others. Invertebrate community also were patterned dependently by type of ecosystems. This results were shown that distribution of invertebrates is a few influenced the relationship of the space habituated invertebrates and environmental factors.

• Parasites, Hosts and Diseases
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• v.45 no.1 s.141
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• pp.45-54
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• 2007

Although Vietnam has a high risk of fish borne zoonotic trematode(FZT) infections for humans, little information exists on the epidemiology of these infections in the country's fish. Because of the importance of cultured cat-fish and snakehead production in An Giang province, a major production area in the Mekong Delta of Vietnam, a survey for FZTs was carried out in randomly selected fish farms between June 2005 and March 2006. For comparison, wild fish from the same area were also surveyed. A total of 852 cultured fish from 4 districts were collected and examined by pepsin digestion to determine their FZT infection status. In Tra catfish, the prevalence of all types of metacercariae was 2.6%, of which the prevalence of Haplorchis pumilio was 0.7%. The overall prevalence of metacercariae in wild fish was 30.6%, of which 10.3% harbored zoonotic species: H. pumilio(2.8%) and Procerovum sp.(5.6%). The prevalence of Opisthorchis metacercariae, which were diagnosed as O. viverrini, was 1.9%. No metacercariae were found in cultured snake head fish, although wild-caught snakehead fish had a FZT prevalence of 10.3%: 5.1% were O. viverrini; 2.6% H. pumilio; and 2.6% were Procerovum sp. These are the first reports of H. pumilio, Procerovum sp., and O. viverrini metacercariae in Vietnamese fish. These results indicate that consumption of improperly prepared fish represents a significant risk of acquiring FZTs in this south Vietnam region.

• Journal of agricultural medicine and community health
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• v.15 no.1
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• pp.3-8
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• 1990

Seven specimens of salmon(Oncorhynchus keta) purchased directly, in Oct. 10. 1990, in the Taep'o port. Kang-won-do were examined for infection state of anisakid larvae and classification of extracted larvae according to morphological characters. The results were as follows. 1) From seven salmon 202 anisakid larvae were found, and mean infection number of anisakid larvae per individual salmon was 28.86. 2) From total extracted anisakid larvae 198 larvae(98%) were found in muscle. Therefore the distribution of anisakid larvae in intestine was extremely rare compared to in muscle. 3) The percentage of anisakid larvae in II, IV muscle region was 93% and from this we could surmise that most anisakid larvae in salmon did not penetrate to the very distanted muscle from intestine. 4) Three types of anisakid larvae(Anisakis Type I, Contracaecum Type B, Contracaecum Type D) were identified and, among them, Contracaecum Type B was the first recording type in Korea 5) Larvae of Contracaecum it genus were found only in intestine. Therefore it surmised that penetration neture to muscle of Contracaecum larvae was less than that of Anisakis Type I.

• Korean journal of applied entomology
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• v.32 no.3
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• pp.279-284
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• 1993

This experiment was conducted to investigate the seasonal fluctuation of population density and the life history of Adoxophyes sp .. Under field-cage conditions, smaller tea tortrix had 4-5 generations a year. The average periods from egg to adult emergence were 43.7 days in spring and fall, and 35.2 days in summer. The average longevity of adults was 7.0 days in spring and fall, and 6.3 days in summer. The average numbers of egg masses and eggs laid by a female were 1.8 and 40.4 m spring and fall, and 2.3 and 49.5 in summer, respectively. Population density of smaller tea tortrix estimated by sex pheromone trap and light trap showed four peaks in each late May, late June, middle August and late September. The number of individuals caught by sex pheromone trap was 2~4 times as large as that by jight trap. Smaller tea tartrix overwimered in larval stage in southern region af Korea.

• Parasites, Hosts and Diseases
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• v.22 no.2
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• pp.161-171
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• 1984

An epidemiological study on Metagenimus yokegawai infection was performed in Samcheok-Bun, Kangwon Province during the period from November 1983 to October 1984. Formalin-ether concentration technique and Stoll's dilution egg counting method were employed to figure out the prevalence and infection intensity of M. yrtkogawai infection. The results are summarized as follow: 1. The Prevalence of M. yokogawai infection was 13.3% among 1,172 examined; 18.0% (114 out of 632) in male and 7.8% (42 out of 540) in female. 2. The Prevalence rates were different by stream; 15.5% in Ohsip-chon (stream), 11.8% in Maeup-chon and 1.6% in Gagok-chon. 3. Along the basin of Oship-chon; 8.2% at the lower reaches in Samcheok-eup, 25.9% at the middle reaches in Miro-myon and 6.2% at the upper reaches in Dogeoe-eup, respectively. 4. By age group, the highest fate (18.3∼20.2%) was observed in 30∼49 years of age (male 24.1∼28.7%, female 11.2∼13.2%). 5. By social strata, the positive rate was 15.0% (120 out of 799) in general inhabitants and 9.7% (36 out of 373) in school children. 6. Intensity by EPG count in feces was 419 in average; the light infection (less than 400 EPG) was 70.4%, moderate infection (401∼1,000 EPG) 19.4% and heavy infection (more than 1,001 EPG) 10.25 respectively. 7. All the 67 sweetfish (length 10.3∼18.5cm) which were caught from Ohsip-stream were infected with metacercariae of M. yokogawai and the number of metacercariae detected were 382 per fish in average (323 in June and 382 in September). 8. Experiences of intake of raw fresh-water fish [Plecoglossus altivelis and Leuciscus (Tribolodon〕 were present in 50.3U (354 out of 704) of the inhabitants along Ohsip-stream according to questionnaire study. The results of this survey indicated that the middle reaches of Ohsip-stream in Miro-myon, Samcheok-gun is the endemic region for M. yokogawai infection.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.5
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• pp.506-515
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• 2011

To elucidate demersal organism community structure, abundance, and biomass by period and region in the Uljin marine ranching area, otter trawl surveys were conducted at six stations from February 2008 to December 2009. During the survey period, a total of 118 species was collected in the Uljin marine ranching area, including 76 pisces, 27 mollusca and 15 crustaceans. The average abundance of individuals was 806 ind./$m^2$ and average biomass was 31,853 g/m2. The numbers of species, species richness, individuals per area and biomass per area were higher in 2009 than in 2008. Cluster and MDS analysis, based on a Bray-Curtis similarity matrix of fourth root transformed data of number of species and individuals per area, showed division into two different groups of demersal organisms in 2008 (Group 1) and one demersal organism community in 2009 (Group 2). From cluster and MDS analysis using the similarity of the demersal community among six stations, the Uljin marine ranching area was divided into Group A (St. 2, St. 4, St. 5 and St. 6) and Group B (St. 1 and St. 3).

• Korean Journal of Ichthyology
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• v.8 no.2
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• pp.57-67
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• 1996

To investigate the fishes of the Arafura Sea of Indonesia, fish specimens were collected by scientists on board Korean trawlers fishing in this region during June 1994 and March 1996. A total of 137 fish species were identified, of which 40 occurred in both 1994 and 1996. In cartilaginous fishes, fishes from the families Carcharhinidae and Dasyatididae were dominant in terms of number of species and in teleost fishes, dominant species were those from the families Engraulididae, Carangidae, Sciaenidae and Tetraodontidae. This study revealed that Sardinelia longiceps, Setipinna melanochir, Cypselurus hiraii, Podothecus sachi, Nemipterus aurora, Johnius grypotus, Moolgarda perusi were collected for the first time in the Arafura Sea.

• Journal of fish pathology
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• v.34 no.1
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• pp.55-61
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• 2021

One of the major problems in fish production is that parasite-induced episodes of disease can result in significant impacts to the health of stock, mortalities and, economical losses. Seabreams are economically important fish in both the capture fishery and aquaculture sectors in Oman and represent potential species for aquaculture. The current study set out to investigate infection of polyopisthocotylean monogeneans on the gills of wild goldlined seabream, Rhabdosargus sarba, caught from Musairah region in Oman. The prevalence, mean intensity and abundance of polyopisthocotyleans on 145 fish was found to be 52.41%, 5.65 and 3.04, respectively. Three species of microcotylid parasite were isolated, one being Atrispinum acarne while the remaining two species require further study to identify them. There was no significant difference in the infection rate between host sex, however, parasite burdens were higher on larger sized fish (p<0.05) and were found to favour the first gill arch (p< 0.05). The study found that the sample of Rhabdosargus sarba landed in the waters around Musairah are heavily infected, with a predominantly immature population of microcotylids. Further work is required to better understand the potential risk each species poses to the health of its host before a decision is made on the suitability of new candidate fish species for commercial aquaculture.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.58 no.2
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• pp.95-105
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• 2022

In this study, the fishery status of the octopus pot fishery in the east coastal sea were investigated, and the fishing performance of each pot shape was compared and analyzed. The fishery status survey was conducted through listening surveys at Jukbyeon Port, Uljin Port and Pohang Daebo Port in Gyeongbuk Province, and the amount of fishing gear used, fishing method, size and loss of octopus pot fishery was investigated. On the east coastal sea, octopus is one of the commercially important fish stocks and is caught in inshore pots, inshore combos, inshore gillnets and offshore pots. Among these fishing methods, pot fishing yields the highest catch. The shape of the pot differs depending on the region. In Uljin (Jukbyeon Port and Hupo Port), Gyeongbuk, rectangular type net pots are mainly used, and in Pohang (Daebo Port) in Gyeongbuk, drum-type pots are mostly used. Enteroctopus dofleini accounts for more than 90% of the catch of octopus. For the octopus fishing performance test by trap type, three types of traps (rectangular pot, drum pot and cylinder pot) were used on the coastal sea of Pohang Daebo. As a result, the total catch by pot shape was shown in the order of rectangular-type pot > drum-type pot > cylinder-type pot. The catch of octopus, the target species, was in the following order: rectangular-type pot > drum-type pot > cylinder-type pot. Such result shows a significant difference (Mann-Whitney test, p<0.05).

• Journal of Practical Agriculture & Fisheries Research
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• v.25 no.3
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• pp.35-46
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• 2023

It was in the 1982 that artificial seed production research for olive flounder (Paralichthys olivaceus) farming was first conducted in Korea (Currently, National Institute of Fisheries Science, Fish Breeding Research Center). In 1985, fertilized eggs were obtained from natural olive flounder adapted to land tanks, and artificial seed production technology was established and fertilized eggs were distributed. In the late 1980s, halibut aquaculture began to prosper in land-based tank farming in Jeju Island and Busan's Gijang region, where water temperatures are relatively high in winter. Currently, aquaculture is being carried out all over the country, centering on Jeju Island and Wando, Jeollanam-do. However, olive flounder farming, which started with a small group in the 1980s, reduced genetic diversity through inbreeding over generations, resulting in side effects such as slow growth, reduced resistance to disease and environmental conditions. In order to solve these genetic problems of farmed olive flounder in Korea, the Fish Breeding Research Center of the National Institute of Fisheries Science introduced a wild-caught parent fish group to the existing aquaculture group from 2003 to 2004. Genetic diversity was secured and KingNupchi with fast growth and improved body shape was developed. In this study, the current status of breeding technology development of olive flounder, a major aquaculture breed in Korea, is reviewed and future research directions are suggested.