• 한국어병학회지
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• 제21권3호
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• pp.167-174
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• 2008

Few studies on parasitic scutica-like ciliates (SLCs) influencing larval growth and survival during the seed production of the Japanese scallop, Patinopecten yessoensis have been performed in spite of relatively high magnitude of their infectious damage to the larvae. In the mass seed production of the scallop, SLCs were never infectious during D-larval stage which lasted 6 to 7 days. Indeed, the infection first occurred in 2 to 4 days after first umbo-staged larvae. A regular selection of active larvae in swimming behavior kept larval SLC infection low throughout the culture compared to unselected control (P<0.05) in which all the larvae alive were contained. Higher infection frequencies of the unselected control resulted in lower larval survivals and wider range of larval size distribution that drove larval attachment rate lower. To the worse, the nursery spats from the higher SLC infection exhibited a retarded growth and elevated occurrence of abnormal scallop.

• 한국양식학회지
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• 제5권2호
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• pp.143-155
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• 1992

산화된 사료에 첨가한 비타민 E, C 와 glycyrrhizin이 나일 틸라피아의 성장 및 Edwardsiella tarda 감염 시 저항력에 미치는 영향을 알아 보기 위해 thiobarbitric acid (TBA) 값이 $80\~88$ mg/kg 사료만을 단독으로 또는 이 사료 100 g 당 비타민 E (50 mg), C (60 mg)과 glycyrrhizin ($25\~200$ mg) 등을 각기 또는 상호 혼합하여 7 주간 사육하였다. 사육후 성장을 조사한 결과 비타민 E, C 및 glycyrrhizin 등을 각기 또는 혼합한 실험군이 산화된 사료만을 투여한 대조군에 비해 성장율이 좋았으며, 혈청 내의 glutamic oxaloacetic transaminase (GOT)와 glutamic pyruvic transaminase (GPT) 값은 산화된 사료를 투여한 실험군에서만 매우 높게 나타났다. 질병원인 E. tarda를 인위적으로 감염시켰을 때 저항력에 있어서도 glycyrrhizin 25 mg 투여군을 제외한 비타민 E, C 및 glycyrrhizin 등을 투여한 실험군이 산화된 사료만을 투여한 대조군에 비해 생존율이 현저히 높았다. 이상의 결과를 종합해 볼 때 산화된 사료만을 나일 틸라피아에 투여했을 때 성장 및 간의 활성도가 떨어지는 반면, 비타민 E, C 및 glycyrrhizin 등을 섞어서 투여했을때 성장 및 간의 활성도가 증가되었을 뿐만 아니라 E. tarda에 대한 저항력도 증가되었음을 알 수 있었다.

• 한국어병학회지
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• 제3권2호
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• pp.61-66
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• 1990

수생균병(水生菌病)의 원인균(原因菌)의 하나인 Saprolegnia diclina Type I 을 뱀장어에 실험적(實驗的)으로 감염(感染)시켜 감염(感染) 기전(機轉)과 균사체(菌絲體)가 체표(體表)의 표피(表皮)와 진피(眞皮)에 나타나는 소견(所見)을 병리학적(病理學的)으로 조사(調査)하였다. 1. 뱀장어를 물에서 건져 그물로 처리한 A, B군(群)에서는 실험적(實驗的)으로 감염(感染)되지 안했으나 인공적(人工的)으로 피부점액(皮膚粘液)을 제거(除去)한 C군(群)에서는 심한 감염(感染)이 관찰(觀察)되었다. 2. 감염어(感染魚)의 체표(體表)에서 채취(採取)한 진균류(眞菌類)는 무격벽(無隔壁)으로 분지(分枝)하며 간접(間接) 발아(發芽) 양식이어서 S. diclina Type I으로 동정(同定)되었다. 3. 어체(魚體) 전반(全般)에 면모상(綿毛狀)의 균사체(菌絲體)가 관찰(觀察)되었고 출혈반(出血斑)을 수반(隨伴)한 병소(病巢)가 형성(形成)되었다. 4. 병소내(病巢內)에는 균사체(菌絲體)가 표피(表皮)와 진피(眞皮)에 신장(伸長) 분포(分布)되어 있었고 특(特)히 피부(皮膚)의 표피층(表皮層)에는 심(甚)한 출혈(出血), 세포(細胞)의 변성(變性), 괴사(壞死_ 및 일부(一部) 점액세포(粘液細胞)는 심(甚)하게 종대(腫大)되어 있었다.

• Fisheries and Aquatic Sciences
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• 제19권5호
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• pp.26.1-26.8
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• 2016

Background: The nematode species belonging to genus Anisakis occur at their third larval stage in numerous marine teleost fish species worldwide and known to cause accidental human infection through the ingestion of raw or undercooked fish or squids. They may also draw the attention of consumers because of the visual impact of both alive and dead worms. Therefore, the information on their geographical distribution and clear species identification is important for epidemiological survey and further prevention of human infection. Results: For identification of anisakid nematodes species isolated from largehead hairtail (Trichiurus japonicus), polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis of internal transcribed spacers of ribosomal DNA were conducted. Mitochondrial cytochrome c oxidase subunit 2 gene was also sequenced, and phylogenetic analysis was conducted. From the largehead hairtail (n = 9), 1259 nematodes were isolated in total. Most of the nematodes were found encapsulated throughout the viscera (56.2 %, 708/1259) or moving freely in the body cavity (41.5 %, 523/1259), and only 0.3 % (4/1259) was found in the muscles. By PCR-RFLP, three different nematode species were identified. Anisakis pegreffii was the most dominantly found (98.7 %, 1243/1259) from the largehead hairtail, occupying 98.7 % (699/708) of the nematodes in the mesenteries and 98.1 % (513/523) in the body cavity. Hybrid genotype (Anisakis simplex ${\times}$ A. pegreffii) occupied 0.5 %, and Hysterothylacium sp. occupied 0.2 % of the nematodes isolated in this study. Conclusions: The largehead hairtail may not significantly contribute accidental human infection of anisakid nematode third stage larvae because most of the nematodes were found from the viscera or body cavity, which are not consumed raw. But, a high prevalence of anisakid nematode larvae in the largehead hairtail is still in concern because they may raise food safety problems to consumers. Immediate evisceration or freezing of fish after catch will be necessary before consumption.

• 한국어병학회지
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• 제22권3호
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• pp.193-200
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• 2009

무지개송어와 산천어에 있어서 백점충의 자연 감염 및 수온별, 어종 유래별 인위 감염에 의한 폐사율을 비교하였다. 백점병은 수온이 낮은 시기에는 산천어가 무지개송어에 비해 잘 감염되었으나, 수온이 높은 시기에는 두 어종간의 차이가 없었다. 백점충의 밀도가 높았던 5월을 제외하고는 양어지의 사육수, 찌꺼기에서 백점충이 검출이 되지 않았다. 수온 10℃에서는 무지개송어에 비해 산천어가 백점충에 대한 감수성이 높았으나, 수온 17${^{\circ}C}$에 서는 폐사에 있어 별 차이가 없었다. 이상의 결과로 무지개송어보다 산천어가 저수온에서 백점충에 대한 감수성이 높음을 알 수 있었다.

• 한국어병학회지
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• 제27권2호
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• pp.133-137
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• 2014

본 연구에서는 2013년 4월 제주 소재 육상수조에서 무지개송어 해수순치 과정중에 대량폐사가 발생하여 질병검사를 실시하였다. 병어의 대부분은 체표에 궤양이 형성되어 있었고, 비장 비대, 유문수 부위 및 복강 근육의 출혈 및 위속에 액성물질이 가득 차 있었다. 병원체 검사결과, 기생충, 진균, 바이러스는 검출되지 않았지만 검사 개체 5마리에서 간, 비장 및 신장조직에서 동일한 형태의 세균 colony가 시료 당 200개 이상 분리되었다. 분리세균의 16S rDNA 염기서열 분석 결과, Vibrio anguillarum과 100% (875/875 bp) 일치하였다. 이상의 결과, 무지개송어 해수 순치과정 중에 발생된 질병은 Vibrio anguillarum 감염증으로 사료되었다.

• Parasites, Hosts and Diseases
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• 제56권6호
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• pp.633-637
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• 2018

Present study was performed to survey on infection status of Isthmiophora hortensis (formerly Echinostoma hortense) metacercariae (IhMc) in dark sleepers, Odontobutis spp., from some water systems of the Republic of Korea. A total of 237 Odontobutis spp. was collected in the water systems of 5 rivers, i.e., Mangyeong-gang (gang means river), Geum-gang, Tamjin-gang, Seomjin-gang, and Nakdong-gang. They were all examined with artificial digestion method for 5 years (2013-2017). A total of 137 (57.8%) Odontobutis spp. were infected with 14.8 IhMc in average. The prevalence was the highest in Nakdong-gang areas (62.9%) and followed by in Mangyeong-gang (57.1%), Geum-gang (56.3%), Tamjin-gang (54.8%), and Seomjin-gang (53.9%) areas. Metacercarial densities were 28.1 (Geum-gang), 13.9 (Mangyeong-gang), 13.3 (Nakdong-gang), 13.1 (Tamjin-gang), and 2.3 (Seomjin-gang) per infected fish. Especially, in case of Yugucheon (cheon means stream), a branch of Geum-gang, IhMc were detected in all fish (100%) examined and their density was about 48 per fish. By the present study, it was confirmed that the infection status of IhMc is more or less different by the surveyed areas and the dark sleepers, Odontobutis spp., are suitable fish hosts of I. hortensis.

• 한국어병학회지
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• 제6권2호
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• pp.219-231
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• 1993

The author introduces the preventive and therapeutic methods of diseases in Japanese flounder which have been conducted by the Fish Disease Laboratory, the Mikamewan Fishery Cooperative Union, Ehime Prefecture, since 1982. Prevention 1. Addition of a sand substrate in the culture pond was effective to prevent ulcer disease. 2. Bathing in 0.5ppm of copper ion was effective to prevent some parasites. 3. Low stocking density of the fish reduced an incidence of edwardsiellosis or gliding bacterial disease. 4. Removal of the diseased fish prevented thd spread of lyphoeystis. 5. So-called $\pi$-water was effective to prevent the fry from some diseases. 6. Immersion of the juvenile in a sodium nifrusylate solution during transportation was effective to prevent gliding bacterial disease. Therapy 1. Sodium nifrustylate or oxytetracycline was effective to cure gliding bacterial disease. 2. Bathing in formalin(150ppm) or freshwater was effective to cure scuticociliatidosis. 3. Erythromycin was effective to cure $\beta$-hemolytic Streptococcus sp. infection. 4. Bathing in a hydrogen peroxide solution(1.5%) was effective to cure white spot disease.

• Parasites, Hosts and Diseases
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• 제61권3호
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• pp.332-337
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• 2023

Infestations of parasites, particularly those caused by copepods and monogeneans, are a major hindrance to aquaculture and have a big negative economic impact. Sebastes schlegelii, a farmed Korean rockfish, is particularly prone to copepods and monogeneans. This study comprehended how parasitic copepods and rockfish from a farm in Tongyeong-si, Gyeongsangnam-do, Korea, are related to the monogenean trematode Microcotyle sebastis. Our research revealed that monogeneans predominated, with a rate of 98.4% and an average infection intensity of 7 per infected fish. With an average infection intensity of 4 per sick fish, the infection rate for parasitic copepods was equally considerable, coming in at 91.7%. The high co-infection rate of both parasite families, at 90.8%, is noteworthy. Furthermore, Lepeophtheirus elegans and Peniculus truncatus, 2 parasitic copepod species, were discovered to have M. sebastis eggs attached to their bodies. This demonstrates a connection between parasitic copepod infestations in farmed Korean rockfish and the monogenean trematode M. sebastis. These discoveries highlight the necessity for creating more potent parasite control methods for the aquaculture sector and shed light on the intricate relationships between various parasite species.

• Asian Pacific Journal of Cancer Prevention
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• 제16권11호
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• pp.4593-4596
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• 2015

Background: Opisthorchis viverrini (OV) infection is the main risk factor for cholangiocarcinoma and is often found in Northeastern Thailand. The prevalence of OV infection and the incidence of cholangiocarcinoma are major public health problems in this region. Objectives: The objectives of this study were to identify factors associated with OV infection among people in Nong Khai Province in order to develop a prevention programme in the community. Materials and Methods: The data were collected in July 2013. Stool specimens were examined for intestinal parasites within hours after collection using a normal saline wet preparation and the modified Kato-Katz technique. A case-control study was conducted to collect information about demographic data, the habit of eating unsafely prepared fish, the safe disposal of waste food, and the practice of defaecating in fields. Structured questionnaires were used to interview 351 participants (117 cases and 234 controls) in a random selection of 30 villages across Nong Khai Province. Multiple logistic regression was used to identify risk factors for OV infection. Results: In the multivariate analysis, the results showed that the factors which had a statistically significant association with OV infection were the habit of consuming unsafely prepared fish ($OR_{adj}=5.17$, 95%CI=2.49-10.74), the similar habit of family members ($OR_{adj}=3.25$, 95%CI=1.63-6.49), a history of O. viverrini infection ($OR_{adj}=5.64$, 95%CI=2.10-15.18), a history of taking praziquantel ($OR_{adj}=5.66$, 95%CI=3.11-10.29), and the unsafe disposal of waste food ($OR_{adj}=2.1$, 95%CI=1.10-3.80). Conclusions: The findings of this study highlight the features on which a community programme should focus in order to reduce the prevalence of opisthorchiasis and incidence of bile duct cancer.