• 한국어류학회지
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• 제26권2호
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• pp.112-117
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• 2014

이 연구는 우리나라에 서식하는 그물베도라치의 산란행동과 난 발생 및 자어의 형태발달을 조사하여 분류학적 연구의 기초자료로 이용하고자 실시하였다. 수정란은 구형으로 백색의 불투명한 침성 점착란이었고, 유구의 수는 3~4개였으며, 난의 크기는 1.31~1.47mm(평균 $1.38{\pm}0.05mm$, n=10) 범위였다. 유구의 크기는 0.12~0.38 mm (평균 $0.25{\pm}0.10mm$, n=10)였다. 사육수온은 $14.5{\sim}16.5^{\circ}C$ (평균 $15.0{\pm}0.05^{\circ}C$)를 유지하였고, 난 발생 과정은 64세포기 후 30시간이 경과하여 상실기에 달하였으며, 64세포기 후 744시간이 경과하여 머리 윗부분이 난막을 뚫고 나오면서 부화가 시작되었다. 부화직후의 자어는 전장 7.10~7.60mm(평균 $7.34{\pm}0.18mm$)로 입은 열려 있었고, 부화 후 6일째의 후기 자어는 전장 9.06~9.13 mm (평균 $9.10{\pm}0.02mm$)로 꼬리지느러미의 윗부분에 줄기가 분화하기 시작하였고, 난황은 모두 흡수되었으며, 먹이 섭식활동을 시작하였다.

• 한국환경생태학회지
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• 제35권3호
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• pp.285-293
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• 2021

본 연구는 우리나라에 서식하는 쌀미꾸리(Lefua costata)의 산란기 특징 및 초기발달과정을 밝히고자 2018년 1월부터 12월까지 강원도 강릉시 옥계면 주수천 일대에서 수행되었다. 산란기는 생식소성숙도 변화와 당년생 치어 출현, 난경의 분포 등을 고려하여 5월부터 8월로 추정되었고, 다회 산란형이었다. 성비는 암컷 1,117개체, 수컷 879개체가 채집되어 1 : 0.79였다. 산란기 동안 확인된 난경은 0.24~0.93 mm로 성숙란과 미성숙란이 함께 확인되었다. 성숙란의 크기는 0.71±0.02 mm, 포란수는 평균 1,786±818 (n=31)개였다. 난 발달과정을 관찰한 결과 수정란은 점착성을 띤 회색의 분리침성난으로 난경은 0.76±0.03 mm였다. 25℃에서 수정 후 34시간(50%) 후에 부화하였으며, 부화직후 전기자어 크기는 전장 2.7±0.11 mm였다. 부화 후 4일에는 전장 4.5±0.16 mm로 난황이 모두 흡수되어 후기자어로 이행하였다. 부화 후 20일에는 전장 11.5±0.67 mm로 모든 지느러미 기조가 정수가 되어 치어기로 이행하였다. 부화 후 100일에는 전장 49.8±2.60 mm로 외형과 체측무늬는 성어와 비교적 유사하였다.

• Fisheries and Aquatic Sciences
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• 제27권4호
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• pp.213-224
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• 2024

Betta rubra, classified as endangered fish species by the International Union for Conservation of Nature (IUCN), has been successfully bred and raised in captivity for two generations under laboratory conditions. This study aimed to provide comprehensive information on the captive breeding of B. rubra, focusing on various parameters crucial for ex-situ conservation and domestication. The research involved breeding trials, embryo and larvae observation, first feeding experiments, larva and fry rearing trials, and the evaluation of growth and reproduction in two generations. The study revealed that the female B. rubra, with an average total length of 5.17 ± 0.15 cm and weight of 1.61 ± 0.06 g, produced an average of 73.67 ± 7.09 eggs, 34.33 ± 5.13 total larvae, and exhibited a hatching rate of 46.67 ± 5.77%. The embryogenesis process commenced on the day of spawning (dps) and continued until the eggs hatched at 6 dps. Larvae development and yolk absorption occurred from 0 to 6 days post-hatching (dph). The study also examined the impact of different initial feeding options, with chopped Tubifex resulting in the most significant in- crease (p < 0.05) in length. The growth pattern of B. rubra larvae showed slow initial growth during the first seven days, followed by a rapid exponential growth phase from day 8 to day 39. Two generations of B. rubra (G1 and G2) were successfully bred in captivity, with G2 showing a better tendency for growth in length and weight compared to G1. Notably, there were no significant differences (p > 0.05) in reproductive success between the wild-origin broodstock (G0), G1, or G2. This research contributes valuable insights into the captive breeding of B. rubra and its early life stages, offering critical information for the conservation and sustainable management of this endangered species. Further research is needed to explore the long-term effects of domestication on behavior, physiology, and phenotypic diversity.

• 한국발생생물학회지:발생과생식
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• 제22권3호
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• pp.289-295
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• 2018

Large quantity of eggs fail to be fertilized and many of fertilized eggs are unable to hatch in the eel, Anguilla japonica. Larvae of eel absorb egg yolk up to 8 days after hatching but the majority of hatched larvae die before they reach the stage of first feeding in this species. Genes of key enzymes for yolk processing (cathepsin B, D, L and lipoprotein lipase - abbreviated as ctsb, ctsd, ctsl and lpl, respectively) could be associated with egg quality. In this study, we investigated differences in the expression of these genes between floating eggs and sinking eggs, and also the relationship between the gene expressions of the enzymes and fertilization rates in the fertilized eggs obtained from artificially matured female eels. Expressions of yolk processing enzyme genes did not show significant difference between floating and sinking egg groups. Expression of ctsb decreased when fertilization rate was high. Expression of ctsd, ctsl and lpl, however, did not show any significant differences. These results suggest that ctsb expression could be an indicator of egg quality, and that some proteins prone to be digested by ctsb could be very important in the process of fertilization and normal cleavage in this species. Further study should identify these critical proteins to improve our understanding on the quality of fish eggs.

• 한국수산과학회지
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• 제37권2호
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• pp.98-104
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• 2004

Early development and metamorphosis of the ascidian (Halocynthia hilgendorfi ritteri) were investigated from fertilized egg. The samples were collected in the coastal waters of Yongdam, northwest of Jeju Island in November 2002. H. hilgendorfi ritteri was solitary ascidian and produced spheral eggs with egg size ranging from $0.33\pm0.01\;mm.$ On the outer surface of the vitelline coat are attached many follicle cells. At $21.0\pm0.5^{\circ}C$ of water temperature, first cleavage took place in about 1.5 hrs after fertilization, and gastrulation followed in about 12.5 hrs. The formation of tailbud embryos and free swimming larvae were observed 13.3 hrs and 20.5 hrs after fertilization, respectively. The size of newly hatched tadpole larva was 1.30-1.45 mm, the larva swam for 2 hrs to 14 hrs. At 4 hrs after hatching, the palpi were lost and tail absorption began with an abrupt rupture of the anterior end of the notochord. At 17-18 hrs after hatching, tail completely absorption and remained trunk. The coniform adhesive papilla began protrusion at 30 hrs after hatching. The oral and atrial siphon formed at 6-7 days after settlement. At 17-18 days after settlement, metamorphosed the larvae developed into protoascidian of which the external morphology was similar to their adult.

• 한국양식학회지
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• 제8권3호
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• pp.159-170
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• 1995

참전복의 3배체 유도를 위하여 수정 12분후 및 32분 후에 저온$(0^{\circ}C\;,\;3^{\circ}C)$해수 혹은 고온$(35^{\circ}C\;,\;40^{\circ}C)$ 해수 속에서 여러 처리 지속 시간으로 3배체 유도 실험을 한 결과, 수정율은 실험군 사이에 유의한 차가 없었다. (P>0.05). 그러나 부화율과 정상발생율은 3배체구간 2배체 대조구보다 유의하게 낮았다. (P<0.05). $40^{\circ}C$의 고온처리구에서 수정율은 매우 낮았고$(0\~2.7\%)$ 부화되는 유생은 없었다. 3배체 유도율은 염색체수를 직접 계수해서 구했는데 가장 높은 3배체 유도율은 수정 12분 후에 $3^{\circ}C$ 해수에 15분 동안 처리했을 때 $(84.0\%)$였다. 참전복 2배체의 염색체 수는 2n=36이었고 3배체의 염색체 수는 3n=54이었다.

• Fisheries and Aquatic Sciences
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• 제14권4호
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• pp.403-410
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• 2011

Scartelaos gigas is an amphibious mudskipper species that inhabits mud flats in Korea, China, and Taiwan. This fish is at risk of extinction because of its very restricted habitat and overexploitation. Information about this fish's reproductive characteristics is needed for species conservation. The sexual maturity and early life history of S. gigas were investigated through histological methods and direct observation of eggs in the wild, respectively. In total, 560 individuals of S. gigas were collected with the aid of fishermen from March 2003 to October 2003 at Jung-do Island, southwest Korea. Through microscopic observations of gonadal development, it was determined that S. gigas of both sexes were immature in April, but began to reach maturity in May, and were then fully mature by June, which was maintained until July. In August, some female fish developed early oocytes, but by September oocytes were observed to have degenerated and had been absorbed. Spawned eggs were elliptical and had an average size of 1.37 mm (long axis) by 0.69 mm (short axis). The newly hatched larvae (3.03 mm total length, TL) had an open mouth and anus, two melanophores near the anus, and one large melanophore between the 18th and 19th myomeres. The larvae (3.18 mm TL) showed absorption of the yolk and oil globule within 5 days after hatching and became prelarvae. This species should be considered vulnerable or conservation-dependent, and thus parental fish need to be protected from fishermen during the main spawning season (June).

• 한국발생생물학회지:발생과생식
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• 제18권1호
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• pp.13-23
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• 2014

This study is conducted to monitor the morphological developmental features of the egg development, larvae and juvenile of Epinephelus septemfasciatus, the fertilized eggs were gotton using artificial insemination. Matured parents are collected from marine caged fish farms in Geomun-ri, Samsan-myeon, Yeosu-si, Jeollanamdo Korea in June 2012. The fertilized eggs were pelagic eggs containing one oil globule, and measured 0.81~0.89 mm ($0.85{\pm}0.04mm$, n=50) in diameter. In regard to rearing environment, the water temperature is $21.0{\sim}23.0^{\circ}C$ and the salinity is 32.0~33.2‰. Hatching was observed from 48 hours after fertilization, the mouth and anus of prelarvae was not opened but had egg yolk at newly hatched. 4 days after hatching, the mouth and anus of postlarvae was opened and began to eat Rotifer and was measured 2.40~2.49 mm ($2.45{\pm}0.03mm$ n=10) in total length. 12 days after hatching, postlarvae was measured 3.77~4.67 mm ($4.27{\pm}0.33mm$) in total length, its the second pole tide of dorsal fin and the first pole tide of pelvic fin was extended longitudinally. 71 days after hatching, juvenile was measured 40.5~45.4 mm ($42.6{\pm}2.04mm$) in total length. Seven bands were observed in body, and pole tides of dorsal and pelvic fins were shortened.

• 생태와환경
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• 제41권1호
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• pp.104-110
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• 2008

멸종위기 야생동식물이면서 천연기념물인 담수어류 미호종개의 난발생 과정 및 초기 생활사를 연구하였다. 성숙란은 인간 성선 자극호르몬(HCG) 10 IU $g^{-1}$을 주사하여 얻었으며, 습식번으로 수정하였다 수정란은 원형으로 투명한 황색을 띈 침성 점착란이었으며, 수정란의 직경은 $1.1\sim1.3mm$로 유구는 존재하지 않았다. 부화는 수온 평균 $25^{\circ}$에서 수정 후 24시간을 전후하여 시작하였다. 부화 직후 자어는 전각이 $2.5\sim2.7mm$ (평균 2.8 mm)로 입과 항문은 닫혀있었다. 부화 후 6일째 자어는 전장이 $4.7\sim5.4mm$(평균 5.1mm)로 꼬리 끝부분 척색이 $45^{\circ}$로 완전하게 굽어 후기 자어로 이행하였다. 부화 후 35일째 개체의 전장은 $20\sim22mm$ (평균 21.8 mm)로 모든 지느러미 가시와 줄기가 정수에 달하여 치어 단계로 이행하였다.

• 한국응용곤충학회지
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• 제61권4호
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• pp.639-640
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• 2022

집나방과(Yponomeutidae)에 속한 작은상제집나방(Saridoscelis sphenias Meyrick)은 2016~2017년 전남 진도와 완도에서 채집된 개체를 동정하여 2020 국내 미기록 종으로 보고되었으며, 마취목(Pieris japonica)과 진달래과에 속한 모새나무(Vaccinium bracteatum Thunb.)와 Leucothoe grayana Maxim. var oblongifolia (Miq.)가 기주식물로 알려져 있었다. 이 종은 2014년 8월 제주특별자치도 블루베리 재배지에서 처음 발견된 후 미정착된 것으로 취급되었으나, 2018년에 이어 2019년에도 제주시와 서귀포시 여러 블루베리 농장에서 발생이 확인되었다. 그 후 2020년부터는 노지 과원에서도 발견되고 있다. 부화유충이 처음 신초 줄기 속으로 침입하여 가해하다가 중간크기로 자란 후 탈출하여 몇 개의 신초를 그물로 철하고 집단적으로 가해하는 등 특이한 피해증상이 나타난다. 향후 피해가 우려되는 해충으로 피해증상과 생활사를 간단히 보고한다.