• 한국수산과학회지
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• 제35권5호
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• pp.542-544
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• 2002

This study was carried out to evaluate the ciliates Euplotes sp. as a live food for marine fish larvae. The ciliates and the rotifers Brachionus plicatilis, which were cultured with the baker's yeast Saccharomyces cerevisiae and the $\omega$-yeast emulsified with cuttle fish liver oil, were supplied to the larvae of flounder Paralichthys olivaceus and grouper Epinephelus akaara. Considering the size difference between the ciliates 68 $\cdot$ 7 $\mu$n and the rotifers 160 $\cdot$ 20 $\mu$n, the rotifers and ciliates were supplied to the larvae tank with the density of 2 inds./mL and 20 inds./mL, respectively. The survival rate and growth in length of the flounder larvae fed on rotifer were significantly higher than those on Euplotes sp.. In grouper larvae which have a small mouth diameter, even the survival rate of the larvae fed on the ciliates was better than that on the rotifers, it was very low less than $20\%$. Therefore, Euplotes sp. seem to be incongruent as a live food for marine fish larvae.

• Parasites, Hosts and Diseases
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• 제50권4호
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• pp.295-299
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• 2012

The present study was performed to determine the infection status of anisakid larvae in marine fish collected from 3 sea areas of the Republic of Korea. Total 86 marine fish (8 species) collected from the East Sea (Goseong-gun, Gangwon-do), 171 fish (10 species) from the South Sea (Sacheon-si, Gyeongsangnam-do), and 92 fish (7 species) from the Yellow Sea (Incheon Metropolitan City) were examined by both naked eyes and artificial digestion method. Among the total of 349 fish examined, 213 (61.0%) were infected with 8 species of anisakid larvae, i.e., Anisakis simplex, 6 types of Contracaecum spp., and Raphidascaris sp., and the mean larval density was 13.8 per infected fish. Anisakid larvae were detected in 45 fish (52.3%) from the East Sea, 131 fish (76.6%) from the South Sea, and 37 fish (40.2%) from the Yellow Sea. The average numbers of larvae detected were 4.0, 16.6, and 15.9, respectively. Anisakis simplex larvae were detected in 149 fish (42.7%), and the mean larval density was 9.0 per infected fish. They were found in 26 fish (30.2%) collected from the East Sea, 96 fish (56.1%) from the South Sea, and 27 fish (29.3%) from the Yellow Sea. The average numbers of larvae detected were 2.9, 10.3, and 10.5, respectively. Conclusively, the present study suggests that the infection rate and density of anisakid larvae are more or less higher in the fish from the South Sea than those from the East Sea or the Yellow Sea.

• 한국수산과학회지
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• 제51권1호
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• pp.72-78
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• 2018

Fish eggs and larvae were collected in July and November of 2013 and January and May of 2014 to determine seasonal variation in the species composition of ichtyoplankton. Samples were classified based on morphological characteristics. Fish eggs were identified as belonging to five taxa; the most dominant species of fish eggs was Engraulis japonicus (62.05%) followed by Sardinops melanostictus (21.02%) and Leiognathus nuchalis (13.71%). These three species accounted for 96.8% of the total number of fish eggs collected. Larvae of 17 species in six families, and six orders were collected. The most dominant species of fish larvae was E. japonicus (51.79%), followed by L. nuchalis (12.59%) and Omobranchus elegans (12.08%). These three species accounted for 76.46% of the total number of larvae collected. Jinhae Bay was identified as a major spawning and nursery ground for fish species inhabiting in the south coast of Korea, such as E. japonicus, L. nuchalis, S. melanostictus, and Omobranchus elegans. Therefore, management of marine fish resources in the South Sea should necessarily include the ecological management of Jinhae Bay.

• 한국양식학회지
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• 제16권2호
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• pp.84-87
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• 2003

Effect of artificial illumination on feeding by the rockfish Sebastes schlegeli receiving no synthetic feed in the cage of the Tongyong Marine Ranch was investigated by analysing the stomach contents of 20 individuals every month from October 1998 to July 1999. The fish was found to have fed on naturally available zooplanktons, i.e. Calanus sinicu, zoeae, amphipods and copepodites in October, fish larvae in November-December, nematodes in January, amphipods in February and again fish larvae from May to July. Despite increase in the weight of stomach contents from 260 mg/fish during the initial period of study to 2,173 mg/fish, as many as 70% of the fish were found to have empty stomach during March-April. Weight of stomach contents did not increase with increasing age of the fish. Occurrence frequency was 83-90% for C. sinicus during October-November and >50% for fish larvae during March-April and June-July.

• 한국수산과학회지
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• 제1권1호
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• pp.1-7
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• 1968

Formerly T. Nishimura, T. Oshima and M. Otsuru studied on Anisakis-like larvae in the various marine fishes from the Japan Sea and the Pacific Ocean. In the present observation, many kinds of marine fishes from the Yellow Sea and the southern coast of Korea were. studied, with the samples from the islands: Eocheng-do, Sohuksan-do, Chuja-do and Keomun-do. The authors examined 313 samples from the adjacent waters of Korea and the distribution of the Anisakis-like larvae in the fish body was found to be 9,219 larvae of Anisakis-like larvae found in the mesentery and coelomic cavity of all samples. Of them, 8,112 Anisakis-like larvae were found from 187 samples from the southern coast of Korea, 1,107 Anisakis-like larvae were found in 126 samples from the Yellow sea (Tables 1 & 2). The fish from the southern coast of Korea are much more infected than the fish from. the Yellow Sea. The larger the fish length, the heavier infection of Anisakis-like larvae were observed.

• 한국양식학회지
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• 제19권3호
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• pp.178-182
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• 2006

이 연구에서는 해산어 초기 자어 사육 과정에서 자어가 섭이하는 로티퍼의 새로운 관찰 및 계수방법을 제시한다. 지금까지는 해산어 자어를 사육하면서 언제부터 로티퍼를 먹이로 이용 가능한지? 그리고 일령이 경과함에 따라 어느 정도 양의 로티퍼를 섭이하는지? 정확하게 분석할 수는 없었다. 왜냐하면 자어가 섭이한 로티퍼(몸통)는 소화기관내에서 소화되어 연구자가 관찰할 수 없었기 때문이다. 그러나 이 연구에서는 이러한 문제점을 해결할 수 있는 새로운 관찰 방법으로서 로티퍼의 저작기(trophi)를 이용하는 방법을 제시한다. 로티퍼는 각 개체마다 한개의 저작기를 가지며 이 저작기는 해산어 자어의 소화기관내에서도 소화되지 않고 그 형태를 유지한다. 따라서 이 연구 결과에 의하면 자어의 소화기관내의 저작기를 관찰하여 계수하는 방법(RTCM; Rotifer Trophi Counting Method)을 이용하여 로티퍼를 최초로 섭이하는 일령은 물론 자어의 일령이 경과함에 따른 포식 로티퍼 개체수를 정확하게 분석할 수 있다.

• 한국어병학회지
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• 제23권3호
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• pp.421-427
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• 2010

Anisakid nematodes third stage larvae were isolated from the muscles of masou salmon (Oncorhynchus masou). Fish were purchased from Jumunjin fishery market in Gangneung. Four Anisakid third stage larvae were isolated from 4 fish. Molecular identification of the isolated worms was conducted by PCR-RFLP analysis of ribosomal DNA internal transcribed spacer region and direct sequencing of mitochondrial DNA cox2 gene. As results, all the tested individual worms were identified as Anisakis simplex (sensu stricto). This is the first report of molecular detection of anisakid worms in salmonid fishes in Korea.

• 한국어병학회지
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• 제34권2호
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• pp.249-253
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• 2021

Anisakiasis is a well-known zoonosis caused by ingestion of raw or thermally undercooked seafood product contaminated with live Anisakis nematode third stage larvae (L3). Several traditional processing techniques have been used to kill or remove the Anisakis larvae worldwide, but thermal processing or deep freezing are the most effective treatments to kill the Anisakis larvae. In this study, we investigated the survival of Anisakis larvae in several condiments (soy bean sauce, wasabi, vinegar, red pepper paste) commonly consumed when eating raw fish in Korea. We also examined several different media (NaCl solution, absolute alcohol, soju) to investigate their larvicidal effect. When directly exposed to various condiments, the most effective larvicidal effect was observed in the mixture of wasabi and soy bean sauce. When exposed to different NaCl solutions, the larvicidal ability became more effective as the concentration increased, but did not show 100% killing effect. In soju, the L3 were killed under less than 4 hr. We observed the larvicidal effects of several condiments in this study, but these results are thought to be carefully interpreted for actual use because all the condiments in this study showed the effect in hours and in general, the L3 are exposed to these condiments only for seconds before ingested in real situation.

• Ocean and Polar Research
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• 제36권2호
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• pp.199-208
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• 2014

Copepods are a major food source for marine fish larvae in nature. Many studies on copepods culture have been conducted to develop a new live food for the seedling production of marine fish larvae. But fish farmers still depend on rotifer and Artemia nauplii. This study was carried out to find suitable copepods as live food for the larvae in hatchery. Eight species of copepods (1 calanoid, 2 cyclpoid, 5 harpacticoid) that were fed Isochrysis galbana were examined in terms of the size of nauplii, fecundity, amino acids, and fatty acids contents. These species were divided into small (nauplii length 46-86 ${\mu}m$) and large (nauplii length 120-188 ${\mu}m$) size group. Nitokra spinipes in the small group and Tigriopus japonicus in the large group showed the highest fecundity with 151.1 and 139.6 nauplii production per gravid female, respectively. With regard to nutrients, essential amino acids were the highest with 21.2% in cyclopoid Paracyclopina nana in the small group and n-3 HUFA were the highest in calanoid Pseudodiaptomus inopinus (8.5 ${\mu}g/mg$) in the large group and P. nana (8.8 ${\mu}g/mg$). In terms of the size, fecundity, and nutritional value of copepods examined in this study, N. spinipes and P. nana seem to be suitable copepod species to develop as a new live food for small mouth fish larvae.

• 농촌의학ㆍ지역보건
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• 제13권1호
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• pp.32-40
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• 1988

Anisakiasis occur after the ingestion of raw marine fish and squid containg anisakid larvae. In recent years about 40 cases of anisakiasis have been recorded in Korea. Considering, however, the Korean style of eating raw fish, many more cases would exist and prevention is necessary. We describe the infection rate of anisakid larvae in 13 species of marine fish and squid which were caught in the Korean sea. And each extracted larva is classified according to morphological characters. The results are following ; Scomber japonicus, Pseudosciaena manchurica, Trichiurus haumela showed high infection rate of anisakid larvae. Although Sepia esculenta showed low infection rate, most of anisakid larvae found in Sepia edulis are embedded in muscles. So relative high frequent rate of anisakiasis may developed by Sepia esculenta. Five type (Anisakis Type I, Terranova Type B, Raphidascaris sp., Contracaecum Type A, Contracaecum Type D) of anisakid larvae are classified according to their morphological characters.