• Korean Journal of Environment and Ecology
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• v.26 no.3
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• pp.367-373
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• 2012

Population ecology (Ecological characteristics) of Squalidus japonicus coreanus from the Namhan River(Yangpyeong-gun Yangpyeong-eup Changde-ri), Gyeonggi-do, Korea were investigated from January to December 2011. Short barbel gudgeon inhabits habitats run of the lower river. The stream bed was mostly covered sand. Their current velocities were 0.14~1.38m/sec and depths were 80~120cm. The sex ratio of female to male was 1 : 0.82. It is presumed that the spawning season is from June to July and water temperatures were $18.5{\sim}24.3^{\circ}C$. Sexually matured individuals appeared over the two year of age. Frequency analysis of total length indicated that the group with 34~50mm in total length was one year old, the 51~74mm was two years old, and the group over 75mm was three years old. The average number of eggs in the ovaries was estimated as 1,871 per matured female. Stomach content of S. japonicus coreanus were Cyanophyta, Chlorophyta, Bacillariophyta, Rotatoria, Crustaceae, Copepoda, Ephemeroptera, Diptera, and Nematoda. omnivorous, mainly feeds on benthic invertebrates such as chironomidae larvae.

• Research in Plant Disease
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• v.18 no.4
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• pp.381-386
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• 2012

Nematode fauna in Dokdo island was investigated for two years between 2008 and 2009. Population density and biomass were $239,500m^2$ (26,000-836,000) and $103.9mg/m^2$ (3.0-388.6), respectively. Total of 31 species of nematodes were identified : Acrobeloides is the most important genus with prominence value (PV) of 117.8, followed by Rhabditidae (PV = 81.9), Prismatolaimus (PV = 39.0), and Aphelenchoides (PV = 31.4). Among feeding group, bacteriovorus nematode composed 77% of density and 62% of biomass followed by plant-parasitic and fungivorus nematodes. A species of Pratylenchus having distinctive tail terminus is under study as a new species. Biological indices, Shannon and Wiener index (2.46), Simpson's diversity index (0.86), Species evenness (0.73), Species richness (1.30) indicate that nematode fauna in Dokdo island is diverse and unique. This study may give a general idea of nematode fauna at the Dokdo island.

• Parasites, Hosts and Diseases
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• v.32 no.1
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• pp.1-6
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• 1994

The numbers of individual Setaria species in the peritoneal cavities of Korean cattle were estimated. The worms were tentatively identified under light microscopy, and then precisely classified by SEM on the basis of unique features at the anterior and posterior ends of the adult worms. The positive rate of Setaria species was 34.2% out of 1,074 Korean cattle surveyed; that of S. digitata was 25.1%, S. marshalli 2.9% and both species 6.2%, respectively. Out of a total of 1,254 worms collected, 66.8% were female and 19.1% were male S. digitota; 9.2% were female and 5.0% were male S. marshalli, respectively. The average length of S. marshalli was somewhat longer than that of S. digitota S. marshalli was documented for the first time in Korea.

• Korean Journal of Veterinary Research
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• v.36 no.2
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• pp.483-494
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• 1996

The present study was undertaken to identify the species of nematodes and determine infection state of small intestinal nematodes from dogs in Taegu area. One hundred and eleven healthy dogs which were 8 months old or more were examined by means of autopsy from September to November, 1993. All of the worms in small intestine were collected and preserved in 10% formalin solution. The worms were cleared in the lactophenol solution and examined by stereomicroscope and lightmicroscope. The result obtained were summarized as follows : Fifty three dogs(47.7%) out of the 111 experimental dogs were infected with small intestinal nematodes. Hookworm infection was recognized in 30(27.7%) dogs. All of the hookworms were identified morphologically as Ancylostoma caninum which had 3 pairs of ventral teeth, a pair of triangular dorsal teeth and a pair of centrolateral teeth. No Uncinaria stenocephala infection was detectable. Roundworm infection was recognized in 37(33.3%) dogs. Twenty one(18.9%) dogs were infected with Toxascaris leonina which had characteristic dorsal lips, paired spicules and a simple tail without process. The individual worm burden of the infected dogs ranged from one to 361 with mean of 25.5%. Among them 0~358(mean $17.8{\pm}30.66$) were Ancylostoma caninum, 0~18(mean $1.6{\pm}3.44$) were Toxocara canis and 0~60(mean $6.0{\pm}12.05$) were Toxascaris leonina. Single infection with Ancylostoma caninum, Toxocara canis and Toxascaris leonina were observed in 16(14.4%) dogs, in 9(8.1%) dogs, and in 11(9.9%) dogs respectively. Double infection with Ancylostoma caninum plus Toxascaris leonina and Toxocara canis plus Toxascaris leonina occurred in 5(0.5%) and in 3(2.7%) dogs respectively. Triple infection with Ancylostoma caninum plus Toxocara canis plus Toxascaris leonina occurred in 7(6.3%) dogs.

• Korean journal of applied entomology
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• v.45 no.1 s.142
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• pp.79-85
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• 2006

This study was conducted to get basic information on the occurrence of plant-parasitic nematodes for the establishment of nematode management strategy in major potato production areas in Korea. Nationwide soil collection was done in 11 areas of Cheju, Yesan, Gimchun, Goryoung, Hong chun, Pyungchang, Gimjae, Milyang, Namwon, Gangnung, and Inje in 2004-2005. Root-hot nematode juveniles(J2) were detected in 30 samples among the 50 samples. The average density was 12-69 J2/100cc soil. Pratylenchus sp., Helicotylenchus sp., Ditylenchus sp., Tylenchus sp., and Tylenchorhynchus sp. were also detected in various locations, however, their densities were very low. Root-knot nematode females were collected from tomato roots inoculated with the potato field soils for PCR-RFLP identification. The females from Cheju, Milyang, and Goryung showed PCR products of 500 bp. And the Dra I restriction enzyme digestions showing 290 bp and 230 bp fragments confirmed their identity as Meloidogyne hapla.

• Korean Journal of Food Science and Technology
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• v.32 no.4
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• pp.970-973
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• 2000

Heavy metal contents and parasite egg examination for the safety evaluation of dropwort(Oenanthe javanica) from the inside of Chonnam province(5 regions) and suburbs of Kwang-ju(1 region) were investigated. The contents of heavy metals(Hg, Pb, As, Cd, Mn, Zn, Cu) were determined by the Atomic Absorption Spectrophotometer and parasite eggs were examined to various internalparasites(F. hepatica, C. sinesis, G. lamblia, Cryptosporidium, A. lumbricoides and A. duodenale). First, Hg and As were detected in trace level and $0.003{\sim}0.01\;ppm$. Pb was not detected in all samples and Cd contents of dropworts were detected $0.014{\sim}0.087\;ppm$. The contents of 4 kinds of heavy metals(Hg, As, Pb and Cd) in dropworts cultivated in various regions(6 regions) were not detected or trace levels. Therefore, dropworts cultivated in Chonnam province and suburbs of Kwang-ju were free from contamination of heavy metals. Moreover, the result of parasite egg examination(Trematoda, Protozoa and Nematoda) was not detected in all samples.

• Korean Journal of Veterinary Research
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• v.30 no.4
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• pp.499-505
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• 1990

The seasonal availability and abundance of the free-living stages of sheep nematodes is a key factor in the occurrence and severity of parasitic infection, and studies of larvae ecology could result in more rational control measures. In the present study seasonal pasture contamination and availability of nematodes for grazing sheep was examined as a baseline work for nematode control program at Namwon Branch, National Animal Breeding Institute during the period April 1988 through March 1989. Standard meteorological measurements were available from Unbong Sub-station, Honam Crops Experiment Station located about 200m from the experimental site. A total of 5 kinds of nematode larvae was detected: Haemonchus contortus was most prevalent (38.0%) with a decreasing order of Ostertagia spp (35.1%), Trichostrongylus spp (19.8%), nematodirus spp (6.6%), and Oesophagostomum spp (0.5%). A succession of species was recorded, in particular Ostertagia spp in May; Haemonchus contortus in June and July; Trichostrongylus spp in July and August; Nematodirus spp in August and September. These results can be incorporated into the nematode control program. To make a more rational control program, however, repeated herbage larval counts should be undertaken soil larval counts and fecal larval counts in the future.

• Journal of Food Hygiene and Safety
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• v.17 no.4
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• pp.206-209
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• 2002

From February through March 2002, sixteen rockfishes representing three species were collected from Oregon Coast Aquarium and Newport fish market and examined far nematodes. During this study, a total of 157 Anisakis type larvae were recovered from Sebastes spp. and parasitized for an average infection prevalence of 50.0%. The yellowtail rockfish, S. flavidus, darkblotched rockfish, S. crameri, and canary rockfish, S. pinniger examined were infected with 110 Anisakis simplex larva, 30 Contracaecum spp. larva and 17 Pseudoterranova decipiens larva. Of the rockfishes examined, 75.0% carried Sebastes crameri, and 12.5% S. flavidus and S. crameri, respectively. The sites of infection far Anisakis type larvae were the intestine, omentum, and stomach walls. A. simplex larvae infected 60.0% on S. crameri and 33.3% on S.flavidus and S. pinniger respectively. The prevalence of Contracaecum sp. larvae and Pseudoterranova decipiens larvae on S. pinniger was 33.3%. The intensities of A. simplex larvae ranged from 1 to 87 in S. flavidus, S. crameri, and S. pinniger. The intensity of Contracaecum spp. larvae and P. decipiens larvae ranged from 0 to 30 in S. pinniger.

• Parasites, Hosts and Diseases
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• v.33 no.3
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• pp.231-234
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• 1995

Anisakid larvae were found from the liver and stomach of the codfish (Notothenia negzecta) caught from the Antarctic Ocean, South Pole, where the Polar Research Center of The Korea Ocean Research and Development Institute is operating- Through observations by scanning electron (SEM) and light microscopy (LM), they were identified as the third stage larvae of Pseunotewnnovo necipiens, a potential agent of human codworm anisakiasis. They measured 25.0-28.5 mm in length, and 0.6-0.8 mm in width. The SEM revealed a prominent boring tooth, three lips, and excretory pore at the anterior end, and a small but prominent mucron at the posterior end. From whole mounts and cross sections of the larvae the ventriculus, intestinal cecum and a Renette cell were found characteristically at the same plane. Raw eating of the codfish caught from the Antarctic Ocean near the South Pole should be avoided so as to prevent human codworm anisakiasis in this area.

• Korean Journal of Plant Resources
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• v.35 no.1
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• pp.23-28
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• 2022

The conversion of rice-fields to uplands is increased in last 8 years due to the government's policy. To obtain basic informations on plant-parasitic nematodes in converted uplands, we surveyed nematodes associated with crops cultured on the ridge of the rice-fields. The crops mostly cultivated at the ridge of rice-field were soybean (66%), red bean (21%), and perilla (13%). Ten important plant-parasitic nematodes species were identified: Helicotylenchus sp., Heterodera glycines, Meloidogyne arenaria, M. javanica, M. hapla, Paratylenchus projectus, Pratylenchus coffeae, P. neglectus, Rotylenchus incultus, Trichodorus sp. Tylenchorhynchus crassicaudatus, and T. claytoni. Among them, Rotylenchus incultus was the most common plant-parasitic nematode in all three crops. The ridge is a border of rice field, thus plant-parasitic nematodes infested on ridges should be cautioned for future cropping.