• 한국균학회지
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• 제29권2호
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• pp.116-122
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• 2001

흰가루병에 대하여 생물적 방제제로 선발된 Ampelomyces quisqualis94013(AQ94013)의 포자현탁액을 처리하여 오이 흰가루병균(Sphaerotheca fuliginea)에 대한 침입과정을 전자현미경과 광학현미경으로 관찰한 결과, 포자현탁액 처리 후 4시간 만에 포자가 흰가루병균의 분생포자, 분생자경 및 균사위에서 발아하고, 17시간 후에는 유사부착기가 형성되어 흰가루병균의 균사에 부착되었다. 24시간 후에는 균사내에 침입하였으며, 44시간 후에는 흰가루병균의 균사와 분생자경의 하부에 AQ94013의 병자각이 형성되기 시작했다. 48시간 후에는 병자각이 성숙되었으며, 52시간 후에는 병자각의 공구에서 병포자가 분출되고, 흰가루병균의 균사 및 분생자경은 변형되어 죽었다. 한편, 오이흰가루병균에 대하여 A. quisqualis 94013의 배양여액을 농축하여 처리한 결과에서 물처리와 차이가 없었으므로 흰가루병균에 대한 감염기작은 A. quisqualis 94013가 독소생성에 의한 것이 아니라 직접기생에 의하여 흰가루병균을 죽이는 것으로 판단된다.

• Parasites, Hosts and Diseases
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• 제54권5호
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• pp.555-563
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• 2016

For several years, we have conducted a series of studies on the patterns of ancient parasitism prevailing in the soil of rural and urban areas of past Kingdom of Korea. Actually, during our survey of paleoparasitology in archaeological sites of Korean peninsula, numerous ancient parasite eggs were discovered in the samples from the city districts of Hansung (Joseon) and Buyeo (Baikje), the palace moat at Gyeongju (Silla), shell-midden site at Bonghwang-dong (Silla to Joseon), and the reservoir found in Hwawangsansung fortress (Silla). By the paleoparasitological studies, with respect to parasitism in the high-density populations of ancient towns and cities, we have managed to catch glimpses of the patterns prevalent therein: a serious parasitic contamination of the soil in ancient urban areas, but not in rural areas of the past. Our historical research also proposed the plausible mechanism of parasite infection very serious indeed among urban populations in Korean history. Although city dwelling doubtless has accrued significant benefits for people and populations with agriculture, it can be equally supposed that living in such highly populated areas might have facilitated the spread of parasite infection.

• Ocean and Polar Research
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• 제43권4호
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• pp.365-370
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• 2021

Manila clam Ruditapes philippinarum is present at high rates of density in tidal flats in Cheonsu Bay on the west coast of Korea, where clams often exhibit mass mortalities in late summer. We monitored the pathologic condition of clams at Hwangdo tidal flat (HD) to understand the parasitic impacts on clam fitness. Manila clams were fully ripe in July and spawned during August and September, as the histology indicated. The histology revealed that clams in HD tidal flats were heavily infected by the protozoa parasite Perkinsus olseni, as the monthly prevalence ranged from 53% (September) to 93% (August). In addition, Manila clams were co-infected by the metazoan parasite Cercaria tapetis and Parvatrema duboisi with the prevalence of 0-33% and 0-14%, respectively. Massive hemocyte infiltration and subsequent inflammation were commonly observed from the gills of P. olseni infected clams. Clusters of P. olseni trophozoites and heavy hemocyte infiltration were also observed from the female gonad, suggesting that P. olseni interferes with host gonad maturation. The larval trematode occupied almost the entire host gonad, resulting in gonad castration. In addition, Metacercaria of P. duboisi were observed from the subsurface of the mantle. Ray's fluid thioglycollate medium assay (RFTM) indicated that clams collected in August and September contained approximately 4.0×106 P. olseni cells/g gills. Condition Index (CI) declined gradually from spring to early summer, and the decline in CI was interpreted as a consequence of the heavy parasitism, as the parasites drain the host's net energy to be used in somatic growth and gamete production.

• Ocean and Polar Research
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• 제44권4호
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• pp.319-329
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• 2022

The paramyxean parasite Marteilioides chungmuensis infects the cytoplasm of the eggs of Pacific oysters Crassostrea gigas , resulting in spawning failure of the infected females. Such infected eggs appear as bump-like nodules on the body in late fall when most of the uninfected females complete spawning. In this study, we estimated the quantity of the infected eggs using an enzyme-linked immunosorbent assay (ELISA), which is destroyed by M. chungmuensis parasitism. In December, the infected oysters collected from Tongyoung on the south coast exhibited numerous yellowish bump-like nodules as signs of infection. In histology, the infected oysters exhibited mature eggs in the follicle, which were heavily infiltrated by hemocytes. ELISA indicated that the infected egg mass accounted for 7.52±5.50 percent of the body weight, suggesting the ovarian parasite causes substantial reproductive loss. Histology also indicated that the infected oysters are in a poor nutritional condition, as the digestive gland atrophy (DGA) level is comparatively higher than the uninfected oyster. The total carbohydrate contents in the infected oysters (108.68±44.41 mg/g dry wt) were significantly lower than in uninfected oysters (269.76±50.97 mg/g dry wt), suggesting that M. chungmuensis parasitism also affected the energy storage capacity of the host during the resting stage.

• 한국응용곤충학회지
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• 제25권1호
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• pp.37-40
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• 1986

필리핀에 있는 국제미작연구소(國際米作硏究所) 논 포장(圃場)에서 이앙(移秧)후 $15{\sim}20$일(日) 된 묘(苗)에서 Scirpophaga incertulas의 난(卵)을 1984년(年) 7월 부터 10월 까지 채집(採集)하여 난기생봉(卵寄生蜂)의 기생율(寄生率) 및 생태(生態)를 조사한 결과(結果)는 다음과 같다. ScirpoPhaga incertulas 의 난(卵)에서 나온 벌목 천적(天敵)으로 Tetrasticus schoenobii, Telenomus rowani, Trichogramma japonicum 3종(三種)이 발견(發見)되었고 기생봉(寄生蜂)의 생물적(生物的)인 습성(習性)에 기초(基礎)를 둔 기생율(寄生率) 계산(計算)방법을 소개하였다. 난기생봉(卵寄生蜂) 3종(三種)의 공기생(共寄生) 조합(組合)은 T. rowani+T. japonicum 조합(組合)이 가장 많았고 T. rowani 는 단기생성(單寄生性) 천적(天敵)으로 우화성충(羽化成蟲) 수(數)가 가장 많았지만 3종(三種)의 기생봉중(寄生蜂中) T. schoenobii 는 유충기간(幼蟲期間) 중 Scirpophaga incertulas 의 난(卵)을 $2{\sim}4$개(個) 소모(消耗)시키므로 가장 유용(有用)한 천적(天敵)이었으며 이 천적(天敵)의 1세대기간(世代期間)은 $10{\sim}14$일(日) 이었다.

• Mycobiology
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• 제40권2호
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• pp.129-133
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• 2012

A new disease, the slippery scar, was investigated in cultivated bags of Auricularia polytricha. This fungus was isolated from the infected mycelia of cultivated bags. Based on morphological observation, rDNA-internal transcribed spacer and 18S sequence analysis, this pathogen was identified as the Ascomycete Scytalidium lignicola. According to Koch's Postulation, the pathogenicity of S. lignicola to the mycelia of A. polytricha was confirmed. The parasitism of this fungus on mushroom mycelia in China has not been reported before.

• Animal Systematics, Evolution and Diversity
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• 제29권1호
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• pp.70-73
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• 2013

Diadegma fenestrale is known as a parasitoid of the potato tuber moth, Phthorimaea operculella. The potato tuber moth, Phthorimaea operculella (Zeller) is one of the most destructive pest of potatoes. Also, we found this species attacking the diamondback moth, Plutella xylostella (Lepidoptera: Plutellidae). Ratio of parasitism is 20-30% and cocoon of lepidopteran was parasitic ichneumonid species after 3 days. This species and the genus Diadegma are recorded for the first time from Korea. In this paper, description of the parasitoid and photographs of the diagnostic characteristics are provided.

• 대한수의사회지
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• 제20권2호
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• pp.97-102
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• 1984

It is difficult to find the reports on the prevalence of the internal parasitisms of the goat in Korea. In the present studies, the internal parasitisms of the Korean native goats in Chonnam area were examined mainly by fecal examinations. For the identif

• 한국수의병리학회:학술대회논문집
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• 한국수의병리학회 2003년도 추계학술대회초록집
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• pp.39-39
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• 2003

Balantidiasis is an infectious disease worldwide which is produced by a protozoan Balantidium coli. This single-celled organism is characterized by their large size ranging from 50 $\mu\textrm{m}$ to more than 500 $\mu\textrm{m}$ [1] which indicated by the presence of cilia on its cell surface. The parasite occurs in the lumen of cecum and colon of swine, humans and nonhuman primates as commensal, but can turn opportunist and invade injury tissues by other diseases [2]. It is difficult to diagnose the disease clinically since they are asymptomatic [3]; and can be complicated with other disease or parasitism. Here we report the incidental findings of Balantidiasis in the lymphatic ducts of gastric lymph node of Barbary sheep (Ammotragus lervia). (omitted)

• 대한수의학회지
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• 제22권2호
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• pp.259-263
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• 1982

Observations were made on the infection rate of common internal parasites in dogs in Kwangju area from January to March, 1982. Dog's stools were collected from veterinary hospitals, houses, intensive dog-rearing places and sidewalks. On the basis of egg counting, the following results were obtained; 1. Of 464 fecal samples, 73.5% were appeared as positive. 2. Dogs from veterinary hospitals and intensive dog-rearing places have higher infection rates than others. 3. Of the parasites detected, Toxocara canis was the most commonly encountered (23.7%). 4. Ascarids, flukes and coccidia were more prevalent in pups than in mature dogs, whereas bookworms were detected less often in young dogs than in older ones. 5. There were significant (p<0.01) differences among age categories for all parasites except tapeworms.