• Animal Systematics, Evolution and Diversity
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• v.13 no.4
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• pp.285-290
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• 1997

Two species of Sphyrna lewini (Griffith and Smith, 1834) and Alopias vulpinus (Bonnaterre, 1788) belonging to the Elasmobranchii were collected form the first time from the western coast of Korea. S. lewini is similar to S. zygaena, but differs in some morphological characters: a prominent median indentation on anterior margin of head and free rear tip of second dorsal nearly reaching upper caudal origin. a. vulpinus differs from A. pelagicus in having labial furrows, long terminal lobe and white ventral coloration extending above the pectoral fin bases.

• Korean Journal of Veterinary Service
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• v.16 no.2
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• pp.103-110
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• 1993

The Aeromonas strains were isolated from diseased cultured catfsh (Silurus asotus) in the ponds near by Gochang of Chunbuk. The present isolates were identified as A. hydrophila based on their biological and biochemica1 characteristics. The isolates of A. hydrophila were named GC-1, GC-2, GC-3, GC-4 and GC-5, Five strains were grew optimally at temperatures $35^{\circ}C,$ pH 7.5 and in 0.5 to l% NaCl. This bacterium(GC-1) was injected into health catfish in order to prove the causative agent of ascites and haemorrhagic ulcers. The symptoms in cat fish infected by this challenge method were observed to be very similar to the symptoms of a natural infection, but controls did not show any abnormal symptoms during the experimental period. At 24 post-injection, the red spot developed around the injection site and the haemorrhagic ulcers was extended near the gill and ventral fin. Five strains were tested for drug sensitivity by plate method. All strains were sensitivity to gentamicin and resistant to penicillin, streptomycin and tetracycline.

• Development and Reproduction
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• v.25 no.1
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• pp.33-41
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• 2021

This study was carried out to observe the development of the autonomous skeletal development of the Favonigobius gymnauchen. Total length (TL) of larvae 3 days after hatching (DAH) were mean TL of 3.34 mm, with a line-shaped parasphenoid ossification in the cranium and basioccipital ossification in the back. The 10 DAH larvae had a mean TL of 5.20 mm, with the number of caudal vertebrae increasing to 15. The urostyle and two hypural bones in the lower part also began to ossify. The 23 DAH juveniles had a mean TL of 8.47 mm. The pectoral girdle's skeleton was completed as the scapula and coracoid were ossified. The pelvic girdle also fully supported the ventral fin as its ossification was completed. Favonigobius gymnauchen and Tridentiger obscurus showed similar characteristics in terms of the anus location of hatched larvae, number of myotomes, and melanophore distribution during the morphological development of the larvae and juveniles. However, this study confirmed differences in the development of the vertebrae and urostyle bone.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.57 no.2
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• pp.153-168
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• 2024

Morphological and skeletal development in the cultured threeline grunt Parapristipoma trilineatum was studied from 1.96 to 61.39 mm notochord length (NL) or standard length (SL) specimens (n=360). After two days post-hatching (dph, 2.13 mm NL), the mouth opened, and melanophores formed in the eyes and egg yolk were absorbed. Oli globules were absorbed at 3 dph (2.71 mm NL). The total number of fin rays reached that of adults at 28 dph (10.58 mm SL). During skeletal development, the premaxillaray, dentary, opercle, preopercle, and cleithrum first began to ossify at 6 dph (3.51 mm NL). Ossification of all skeletal elements was completed at 28 dph (14.57 mm SL). The vertebrae began to ossify at 17 dph (5.63 mm SL) and were completed at 28 dph (8.48 mm SL), progressing from cranium to caudal bone. The centrum ossified from the dorsal to ventral direction. Vertebral fusion and separation were found to be common skeletal abnormalities.

• Korean Journal of Ichthyology
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• v.19 no.4
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• pp.343-349
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• 2007

Embryonic and larval developments on Pacific cod, Gadus macrocephalus are described from laboratory-reared specimens. The eggs (1.075~1.168 mm in diameter) were weakly adhesive, almost spherical in shape, transparent and unpigmented, showing a pale yellow yolk without oil globules. Hatching was occurred 220 hrs after fertilization at $9.8^{\circ}C$. The newly hatched larvae (3.72~4.40 mm in total length, TL) had 43~47 (11~13+32~34) myomeres, mouth and anus which was not yet opened. The yolk was completely absorbed at 4.58 mm TL, and transformed to postlarval stage. Locations of the anus and second dorsal fin origin, and distinctive growth of the larvae head were observed at 5.48 mm TL with melanophores in the gill cover and upper region of the occipital. In addition, melanophores were distinctive in the ventral region and caudal fin base at 6.88 mm TL. All fins were formed with a complete set of fin rays having the following counts (D. 3~7-12~14-13~14; A. 13-15) at 11.54 mm TL. Both lateral line and barbel of lower jaw were observed at 15.07 mm TL.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.17 no.2
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• pp.125-131
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• 1984

The horn fish, Hemiramphus sajori TEMMINCK et SCHLEGEL, is widely distributed in the coastal waters of Korea, Japan and Taiwan. On April 13, 1983, mature adults of the horn fish were collected from Changson channel, Namhae. The authors carried out artificial insemination on the field, and incubated the eggs and reared larvae in the laboratory. And these larvae were reared for about two weeks in glass jars, fed brine shrimp nauplii. The eggs of this species are demersal and adhesive, with 4 to 6 filaments at the animal pole and a filament at the vegetal pole. The diameter of these eggs varies 1.80 to 2.00 mm. The hatching took place in ca. 376 hours after fertilization. During the incubation period water temperature fluctuated between $13.5^{\circ}C\;and\;20.0^{\circ}C$. The newly hatched larvae were elongate in shape $7.40{\sim}8.00$ mm in total length with $40+16{\sim}17=56{\sim}57$ myomers. Many melanophore were distributed on the head, both sides of dorsal body contour, peritoneum and ventral line of the tail part. Four days after hatching, the larvae were from 9.00 to 9.65 mm in total length, at this tims the larvae absorbed the yolk completely, and became postlarvae. Fourteen days after hatching, the larvae attained 13.25 mm in total length, with 14 rays of the dorsal fin, 13 rays of the anal fin, and 4 rays of pectoral fin. The lower jaw has somewhat projected.

• Korean Journal of Ichthyology
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• v.26 no.1
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• pp.25-33
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• 2014

This study was conducted to observe the spawning behavior and early life histroy of elegant blenny, Omobranchus elegans reared in the laboratory. The elegant blenny were caught at Dolsan lsland, Yeosu-si, Jeollanamdo from June in 2012. As a result of observeation, male fish attracted female continuously and guide lead to spawning site and clean the surface of inner pant in oyster shell or barnacle shell. Female left after spawning and male protected their eggs until they had hatched out. The fertilized eggs were spherical in shape (mean diameter: 1.06 mm; mean oil globule diameter: 0.24 mm) and transparent. Larvae hatched at 203 hrs 40 mins after fertilization at $25.5{\sim}28.5^{\circ}C$ (mean $27.0^{\circ}C$). The newly hatched larvae were 3.04~3.09mm(mean 3.06 mm, n=10) in total length and their mouth and anus were already opened. They began to eat rotifer and transformed to postarvae stage. 10 days after hatching postlarvae was measured 6.39~6.45mm(mean 6.42 mm, n=10) in total length. 60 days after hatching juvenile was measured 21.5~22.2 mm (mean 21.8 mm, n=10) in total length with dosal fin rays XI-22; ventral fin rays I-2; anal fin rays II-23; caudal fin rays 21; pectoral fin rays 13.

• Korean Journal of Ichthyology
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• v.36 no.1
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• pp.94-100
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• 2024

During ichthyoplankton survey in the southwestern sea of Korea, we collected six individuals of noodlefish larvae and juveniles between April and May 2023. They were identified as Neosalanx anderssoni by mitochondrial DNA cytochrome c oxidase subunit I or 16S ribosomal RNA sequences, and their external morphological traits were described for the first time. All six individuals have a slender and elongated body. When preflexion and flexion larval stages (10.24 mm notochord length, NL and 15.47 mm total length, TL, respectively), oval-shaped black melanophores were distributed in a row along the ventral side of the gut. However, when postflexion larval and juvenile stages (23.58~25.90 mm TL, and 29.20~31.26 mm TL, respectively), melanophores on the ventral side of the gut were disappeared, and dark spot-shaped melanophores appeared along the dorsal side of the gut in a single row. Also, from the postflexion larval stage (23.58 mm TL), two large black spots began to appear symmetrically on the caudal fin. Our results suggest that N. anderssoni may use coastal area as spawning and/or nursery ground unlike previous study (Kim and Park, 2002).

• Korean Journal of Fisheries and Aquatic Sciences
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• v.41 no.6
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• pp.471-477
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• 2008

Development of egg, larvae and juveniles for the Pacific mackerel, Scomber japonicus are described following natural fertilization in the indoor tank of $25^{\circ}C$ water temperature. Following a routine hormone treatment technique for the brood stock, male and female mackerels were artificially matured by intramuscular injections of LHRHa at a dosage of $400{\mu}g/kg$ body weight (BW)+Domperidone at a dosage of $4{\mu}g/kg$ body weight (BW) to induce maturation in a separate aquarium and induced natural spawning. Fertilized eggs were ca. 1.0 mm in diameter; spherical in shape with a single oil globule; pelagic and non-adhesive. Hatching occurs 41 hours after fertilization at $23-24^{\circ}C$. The newly hatched larvae was 3.03 mm in average total length (ATL), the mouth and anus were not open, oil globule located in posterior end of yolk sac, and preanal length was 42.8% of TL. The larvae measuring 2.89 mm ATL, almost absorbed yolk sac and oil globule material in 2 days after hatching, in which the mouth and anus were open. Melanophores, branch or star in shape were observed on the top of head, peritoneal region and along the ventral contour. In 13 days after hatching, the larvae was 6.88 mm ATL, its posterior end of notochord began to flex upward, finfold of caudal fin appeared, jaw teeth were already formed. In 19 days after hatching, the larvae was 7.71 mm ATL completed only caudal fin rays (9+8), and preanal length was 49.4% of TL. In 37 days after hatching, the larvae was 27.4 mm ATL already completed all the fins, and preanal length was 59.9% of TL.

• Korean Journal of Ichthyology
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• v.11 no.2
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• pp.143-148
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• 1999

Two sibling species of the genus Platycephalus collected from the South and West Sea of Korea were reviewed based on the several meristic and morphological characters, electrophoresis of muscle protein, and LDH and MDH isozyme. Counts and morphometric characters of Platycephalus indicus were different from those of Platycephalus sp. by having 18~20 pectoral fin rays (16~19 in Platycephalus sp.), 70~80 scales of lateral line (83~100), 10.2~13.1% eye diameter (10.9~15.5%), 14.5~18.1% interorbital width (11.8~17.8%), dark brown of body color (light brown) and dark brown of pectoral and ventral fin outside (light brown and pale). The number of soluble protein bands in muscle separated by polyacrylamidegel electrophoresis was 16 and 18 from P. indicus and Platycephalus sp, respectively, and each bands showed their characteristics in activated degree. The number of bands separated from LDH isozyme were 2 and 1 in P. indicus and Platycephalus sp. and in the case of MDH isozyme, 5 and 4 bands, respectively. So we were thought that P. indicus and Platycephalus sp. from Korea were different species each other.