• Journal of fish pathology
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• v.22 no.3
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• pp.201-210
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• 2009

Although Anisakis type larvae have been shown to cause various injuries directly or indirectly in humans and animals, the epidemiological studies on these larval infestations are in insufficient state. The status of larval infestation was investigated in 989 fishes of 44 species, which are inhabiting around the east-westernsouth costal area of Korea during the period from March 2007 to February 2008. The Anisakis type larvae were infected approximately 38% (377 fishes) in 989 fishes. Most of the worms were identified as Anisakis simplex type I by morphological finding and 18S ribosomal DNA sequence analysis. In the seasonal variations of infestation, most of the fishes showed higher infestation rate during spring and summer, while the fishes such as herring Clupea pallasii did during winter. From the histopathological studies of infested fishes, it has been observed that Anisakis type larvae are harbouring mainly around the intestinal viscera such as liver, pancreas, stomach, pylolic cecum, and cloaca.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.4
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• pp.342-347
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• 2002

Ciliates have the possibility of a new live food in marine finfish culture because of their wide range of body size, thin tell wall, show motility, and fast reproduction rate. In this research, six species of ciliates were isolated from south coast and salt pond in Korea. The fitness of these species as a live food was evaluated in terms of size, motility, suspensibility and cell density. As the result, Euplotes sp. (K-1) was found suitable to be a new live food which might substitute rotifers, Brachionus plintilis and B. rotundiformis in fish larvae culture. The modified $F{\emptyset}yn's$ Erdschreiberd media, MErds-2 with the addition of glycine, glucose and yeast extract increased six times higher growth rate of Euplotes sp. (K-1) than the basic F$\emptyset$yn's Erdschreiberd media. The optimum water temperature, pH and light intensity for this ciliates were $22.5^{\circ}C$, 8 and 2,000 lux, respectively, and its culture environmental range was relatively wide, On the other hand, this ciliate fed baker's yeast, Saccharomyces cererisiae grew up to 1,240 inds./mL with the inocula of 100 inds./mL within 7 days. The results of the study showed that Euplotes sp. (K-1) has a potential to be utilized as a new live food in fish larvae culture.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.16 no.3
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• pp.163-180
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• 1983

Fish larvae were collected from Changson channel, Namhae over the period from June 1982 to May 1983. A total of 44 species (33 families and 41 genera) were identified and described with morphological feature. The larvae of Cyclopsis tentacularis is newly reported in the Korean waters. Abundance of the species in numbers was as follows : Engraulis japonica $86.56\%$, Acanthogobius flavimanus $5.91\%$, Enedrias sp. $1.71\%$, Sebastes inermis $1.18\%$, Leucopsarion petersi $0.78\%$, Hexagrammos otakii $0.68\%$. According to variation of seasonal abundance the larvae were grouped into three seasonal groups as follows : Spring type: Engraulis japonica, Astroconger sp., Enedrias sp., Leucopsarion petersi, Sebastes inermis, Hexagrammos otakii Summer type : Engraulis japonica, Leiognathus nuchalis, Acanthogobius flavimanus, Omobranchus elegans, Syngnathus schlegeri. Winter type: Enedrias sp.

• Korean Journal of Ichthyology
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• v.34 no.2
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• pp.96-101
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• 2022

The egg, larvae, and juvenile development of Platycephalus indicus sampled from Yeosu estuary were conducted. The egg shape of P. indicus is spherical and transparent on the outside, with two perivitelline cavities inside and one oil globule. The diameter of the fertilized eggs were 1.03~1.12 mm (mean =1.08 mm, n =50). The embryos hatched in about 50 hrs 30 mins after fertilization at the water temperature of 20℃. The newly hatched larvae showed a total length of 2.72~3.04 mm (mean=2.93±0.21 mm, n=50). At 5 days after hatching, they were 3.88~4.42 mm (mean=4.11±0.31 mm, n=15) in TL and their yolk was completely absorbed, developing the teeth. They became juvenile 39 days after hatching and reached 10.23~11.95 mm (mean=11.09±0.86 mm, n=5) in TL. At 45 days after hatching, they were 12.01~13.25 mm (mean=12.63±0.62 mm, n=5) in TL, and their body shape and color were similar to those of adult fish.

• Korean Journal of Ichthyology
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• v.1 no.1_2
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• pp.1-8
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• 1989

In August, 1988, matured adults of devil stinger were collected from Jinhae Bay and Jaran Bay, Kyongsangnam-do, Korea and kept in the aquarium (1 ton) for spawning. The egg development was observed with the eggs laid in the aquarium of adult fish. The diameters of eggs ranged from 1.2 to 1.3 mm (n=6), and no oil globules were found in the eggs. The hatching took place from 26 to 29 hours after eight cells stage at the water temperature of $24.9-26.5^{\circ}C$. The newly hatched larvae were 2.47~3.10 mm in total length with xanthophore on the body and yolk sac. Myomere number was 13+16-17=29-30. Two days after hatching, larvae were 3.61-4.16 mm in total length, and 3 to 4 large spots of melanophore appeared on the large pectoral fin. Three days after hatching, larvae were 3.97-4.29 mm in total length, and the larvae absorved the yolk material completely to become post larvae with 4-5 rays of the pectoral fin. Six days after hatching, larvae attained 4.07-5.46 mm in total length, and 11 rays and 8-9 spots of melanophore were developed on the pectoral fin.

• Korean Journal of Ichthyology
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• v.31 no.4
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• pp.214-221
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• 2019

This study suggests basic data for taxonomic research among similar species by observing osteological development of larvae of Hemibarbus longirostris. Newly hatched yolk-sac larvae were 8.10±0.02 mm (n=5) in mean total length, and frontal, parasphenoid, and basioccipital in the cranium were ossified. On the 6 days after hatching, flexion-larvae were 10.9±0.26 mm (n=5) in mean total length, hyomandibular, sympletic, and ectopterygoid in the cranium were ossified. On the 12 days after hatching, post-larvae were 12.2±0.55 mm (n=5) in mean total length, interopercle in operculum region and postclavicle in shoulder girdle bone were ossified. On the 25 days after hatching, post-larvae were 16.1±0.27 mm (n=5) in mean total length, epihyal and interhyal in hyoid arch, two epural in caudal skeleton, interneural processes, and interhaemal processes were ossified. On the 40 days after hatching, juvenile were 27.9±3.74 mm (n=5) in mean total length, all skeletal development completed with hypural bone in the caudal skeleton region fused in three forms (1, 2+3, 4+5).

• Korean Journal of Fisheries and Aquatic Sciences
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• v.43 no.6
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• pp.751-755
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• 2010

To understand the function of nursery grounds, the seasonal variation of ichthyoplankton was investigated in the East Sea, off Dokdo, from September 2009 to May 2010. The dominant species was Engraulis japonicus (92.7%), which occurred in May and September. The next abundant species was Maurolicus japonicus (5.7%), found in all four seasons. Several rare warm-water species were found in September and November, when the species diversity was higher than in the other two seasons. Several fish species used Dokdo as a nursery ground for a restricted season, while M. japonicus used it in all four seasons.

• Parasites, Hosts and Diseases
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• v.44 no.1 s.137
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• pp.81-86
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• 2006

Anisakiasis is a parasitic disease caused by ingestion of raw fish infected with anisakid larvae. Endoscopic changing patterns of submucosal lesions in chronic gastric anisakiasis have not been known yet. Here we report 4 cases of suspected gastric anisakiasis which were improved during follow-up periods without surgical treatment. The patients presented with abdominal pain, nausea and vomiting after consuming raw marine fish, and visited our gastroenterology outpatient department. Their endoscopic findings showed firm and yellowish submucosal masses accompanied with eccentric erosions. Histologic findings showed severe eosinophilic infiltrations. In blood tests, peripheral eosinophil counts and total IgE levels were elevated. We believed that all cases were caused by larval anisakid infections. The submucosal mass lesions disappeared during the follow-up periods of 2 to 4 mo.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.52 no.4
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• pp.408-417
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• 2019

This study was conducted to identify taxonomic differences in the characteristics of Rhodeus uyekii and Rhodeus ocellatus during their initial life history via an interspecific hybridization experiment. Hybrids were compared to their parent species, and the findings were used to inform developmental research in commercially useful aquarium fish. The hatching rates of the cross-bred eggs were 75.9% for cross UO (R. uyekii ♀${\times}$R. ocellatus♂) and 71.9% for cross OU (R. ocellatus♀${\times}$R. uyekii♂), which did not differ greatly from the hatching rates of the normal cross-bred group. Backcross experiments resulted in 100% egg mortality during development. Newly hatched larvae of the original hybrid crosses were similar to those of the maternal line, and the color of the egg yolk was similar to that of the paternal line; therefore, the respective traits of the interspecific parents were identifiable within the cross-bred offspring.

• Korean Journal of Ichthyology
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• v.30 no.3
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• pp.137-143
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• 2018

This study was carried out to observe the development of the autonomous skeletal development of the Tridentiger trigonocephalus. Seven days after hatching, the skeleton of the two line cranes began to ossify at premaxillary, maxilla and dentary when the average total length was 4.44 mm (n=5). At thirteen days after hatching, the frontal, parietal, and epiotic ossicles were observed in the cranium when the average total length was 5.62 mm (n=5). At thirty-two days after hatching, actinost and post cleithrum were ossified at the shoulder when the average total length was 11.8 mm (n=5). At forty days after hatching, the lateral ethmoid of the skull was ossified with an average total length of 13.3 mm (n=5) and all skeletal development was completed.