• 한국어류학회지
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• 제35권2호
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• pp.75-82
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• 2023

본 연구에 사용된 시료는 2021년 4월 21일과 5월 16일 2회에 걸쳐 경북 영덕군에 위치한 대서천에서 자가사리와 난괴를 채집하였다. 수정란 크기는 3.30~3.92 (3.57±0.19) mm (n=30)였고, 수온 17.0~20.0℃에서 부화까지 소요된 시간은 152~155시간이었다. 부화 직후 자어는 전장 6.43~6.67 (평균 6.55±0.07) mm (n=30)로 입과 항문은 완전히 열리지 않았고, 난황을 가지고 있었다. 부화 후 9일째 후기자어는 전장 11.0~13.8 (12.3±0.70) mm (n=30)로 꼬리 끝의 미부봉상골이 위쪽을 향해 45°로 완전히 휘어졌다. 부화 후 16일째 치어는 전장 15.8~18.2 (16.8±0.77) mm (n=30)로 지느러미 줄기 수는 등지느러미 8개, 뒷지느러미 17개, 배지느러미 8개로 정수에 도달하였다. 연구 결과 근연종들 간 초기생활사에서 부화자어 크기, 지느러미 반문형태 등에서 차이를 확인할 수 있었다.

• Asian-Australasian Journal of Animal Sciences
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• 제10권2호
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• pp.192-195
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• 1997

Thirty adults Desi and Khaki Campbell ducks were distributed to 6 farmers of Chakcharpur village of Mymensingh district. These ducks were subjected 3 types of mating e.g. Desi ${\times}$ Desi, Khaki Campbell ${\times}$ Khaki Campbell and Khaki Campbell ${\times}$ Desi-having 10 ducks (male : female = 1 : 4) in each mating group. Each mating group was then divided into two having 5 ducks(male : female = 1 : 4) and distributed to 2 farmers. After collecting eggs from each mating category, these were hatched by broody hens from which a total of 90 day old ducklings, 30 from each genotype were raised from birth to 90 days after the onest of laying. Although the weight of the day old chicks were similar in all genotypes (40-43 g), body weight was the highest (p <0.01) for Khaki Campbell ${\times}$ Desi (1,543) before the onset of laying followed by Khaki Campbell (1,552 g) and Desi (1,448 g) ducks. Khaki Campbell attained maturity at an earlier (p < 0.01) age (147 days) followed by Khaki Campbell ${\times}$ Desi, (154 days) and Desi (161 days) ducks. Khaki Campbell laid maximum (p < 0.01) number of eggs (46) compared to Khaki Campbell ${\times}$ Desi, (30) and Desi (18) ducks 90 days after the onset of laying. However, eggs were heavier (p < 0.01) in Desi (61.9) ducks compared to other genotypes. Fertility and hatchability were also higher in Desi ducks than the other two genotypes. Mortality was also lover in Desi ducks (3.33%) followed by Khaki Campbell ${\times}$ Desi (6.66%) and Khaki Campbell (16.66%) ducks. The results presented here indicated the superiority of Desi ducks over the other two genotypes with respect to egg weight, fertility, hatchability and mortality under village condition. Pure and crossbreds, on the other hand, were heavier at sexual maturity at relatively younger age and laid more eggs.

• 한국어류학회지
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• 제9권2호
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• pp.178-185
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• 1997

1996년 11월부터 부산, 통영, 거문도 및 완도 연안에서 낚시와 자망에 의해 채집한 어미들을 육상수조로 운반하여 체내에서 수정된 난을 인위적으로 채란하여 난의 형태, 난발생과정 및 자어의 성장에 따른 형 태 변화를 관찰하였다. 1. 쏨뱅이의 수정란은 구형으로 무색 투명하며, 난경은 0.76~0.82 mm (n=50)이고, 부화에 소요된 시간은 상실기 이후 $13.7^{\circ}C$에서 약33시간 30분이였다. 2. 부화 직후의 자어는 전장 1.62~1.68 mm로, 몸은 길고 입과 항문은 열려있지 않고, 근절은 7~8+16=23~24개로 아직 정수에 달하지 않았으며, 막상의 가슴지느러미가 약하게 존재한다. 3. 부화 14일째의 자어는 전장 3.52~3.80 mm로, 가슴지느러미가 막상으로 크게 분화하고, 처음으로 복강에 흑색소포가 출현하며 이 시기에 난황이 완전히 홉수되어 후기 자어로 이행한다.

• 한국수산과학회지
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• 제41권6호
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• pp.478-484
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• 2008

To elucidate the spawning behavior and early life history of Liobagrus mediadiposalis, mature male and female fish were collected from a branch of the Seomjin River. Spawning was induced by injecting hormones, and then the spawning process and development of fertilized eggs, larvae, and juveniles were observed. Observations of spawning behavior showed that the female established a territory and built a spawning nest, and frequently pressed on the upper ventral part of the male to release her eggs. When spawning was finished, the fish supplied fresh water to the egg mass using their pectoral and caudal fins. Hatching began 189 h 20 min after fertilization at $21.5-23.5^{\circ}C$ (mean $22.7^{\circ}C$). The mean total length (TL) of newly hatched larvae was 7.18-7.39 mm (mean 7.31 mm). Their mouth and anus were already open and they had 14+24=38 myotomes. Eighteen days after hatching, the larvae were 12.71-13.79 mm (mean 13.27 mm) in TL and the yolk sac was absorbed completely. At 35 days after hatching, when all the fin-rays had formed, the juveniles were 15.84-17.92 mm (mean 16.33 mm) in TL.

• 한국어류학회지
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• 제24권2호
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• pp.94-100
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• 2012

우리나라 고유종인 기름종개의 난발생 및 초기생활사를 연구하기 위해 2007년 6월에 전라북도 남원시 운봉읍의 낙동강에서 성숙한 개체를 채집하였다. 채집된 개체는 LHRH-1을 주사하여 건식법으로 인공수정시켰다. 성숙란은 분리침성란으로 밝은 회색이었으며, 난경은 $1.29{\pm}0.07mm$였다. 수정난은 수온 $23{\sim}25^{\circ}C$에서 수정 후 45~52시간 사이에 부화하였으며 크기는 전장 $4.5{\pm}0.24mm$였다. 부화 후 5일 후에 난황이 모두 흡수 되어 후기자어로 이행하고 전장 $6.6{\pm}0.13mm$로 성장하였으며, 부화 후 25일에는 지느러미 기조가 모두 정수로 되어 치어기로 이행하였고 전장 $9.0{\pm}0.49mm$로 성장하였다. 부화 후 100일 후에 반문모양과 외부형태가 성어와 유사하였고 전장 $27.3{\pm}2.82mm$로 성장하였다.

• 한국양식학회지
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• 제12권4호
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• pp.255-266
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• 1999

The early development, growth, and morphological changes of Tiger puffer Takifugu rubripes are described on the basis of a seres of a series of reared specimens. Detailed o수 the early developmental stages are illusrtated withe special reference to morphological transformation. Egg and sperm of puffer fish Takifugu rubripes were obtained from mature adults under natural conditions, ferilized artificially and incubated in the laboratory. The incubation period of fertilizd eggs was 160 to 180 hours at a temperature of $15.1~ 18.0^{\circ}C$. Larvae were fed successively with rotifer, Artemia nauplii and artificial food for 90 days. The mean total length of newly-hatched larvae was about 2.8mm. Mouth opening occurred on the 1- day yolk-sac larvae and initial feeding was observed on th 4-5 days after hatching . The morphological transitions from the larvae to juvenile and juvenile and juvenile to young stages occurred when fish reached about 10mm in total length(about 30 days after hatching) and about 32mm in total length(about 60days after hatching) , respectively. The coefficient of variation in total length distribution increased with growth. Following the appearance of its peak at the size of about 18mm in total length, the coefficient value declined. Many changes in proportion of the body parts to total length were observed at about 9~10mm and 30~33mm in total length, corresponding to the transformations from larvae to juvenile and from juvenile to young, respectively. Also one big morphological change was observed at about 18mm in total length that divide the juvenile stage into two sub-stages.

• 한국양식학회지
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• 제9권1호
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• pp.11-18
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• 1996

본 연구는 수정난에서 부터 부화후 60일 까지 황복의 배발생 및 자치어의 발달에 관한 형태적 특징을 조사하였다. 배발생 단계는 융합기, 난할기, 포배기, 낭배기, 체절형성기, 인두형성기 및 부화기 등 7가지로 구분하였다. 황복의 난은 분리부착 침성난으로 구형이며, 난황은 작고 많은 유구를 갖고 있다. 수정후 약 170시간 경에 난황 주위에 흑색소포가 출현되기 시작했다. 수온 $17.0{\pm}1.0^{\circ}C$에서 수정후 280시간에 부화되며, 부화된 자어는 큰 난황을 달고 있으며, 그 크기는 $3.00\~3.54\;mm$이고 $25\~26$개의 체절이 형성되었다. 부화후 7일에는 난황과 유구가 완전히 흡수되고 자어기에 도달했다. 부화후 60일에 자치어의 전장은 $23.54\~30.12\;mm$로 성장되며, 모든 지느러미가 형성되었다.

• Fisheries and Aquatic Sciences
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• 제10권2호
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• pp.74-85
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• 2007

Pacific anchovy (Engraulis japonicus) eggs were collected during the spawning season (2000-2003) using a revised ring net in the coastal waters adjacent to the Geum River Estuary in the West Sea of Korea (Yellow Sea). Anchovy eggs were present from May to September, showing a peak in spawning from June to July when the water temperature and salinity were $17-27^{\circ}C$ and above 30.00 psu, respectively. During the main spawning season, no clear diel cycle (regarding the 24-h sampling period of dusk, night, dawn, and daytime) was detected in the vertical distribution of anchovy eggs near Eocheong Island (50-60m depth). Judging from the developmental stages of the collected eggs, it appeared that anchovies spawned mostly at night and that the eggs hatched at dusk and during the night. The density of anchovy eggs was high in the southwest-northeast direction in June, and spawners appeared to move offshore in July. Mean egg density was higher in June 2002 than in June 2003 when water temperatures and salinities were lower. This study on the spatiotemporal distribution of eggs will contribute to developing management plans for the Pacific anchovy in Korea.

• 한국수산과학회지
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• 제53권4호
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• pp.506-514
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• 2020

We investigated seed management and feeding regime of larval red spotted grouper Epinephelus akaara using live food organisms. Fertilized eggs were produced in March 2020 by manipulating photoperiod and water temperature. Broodstock (F0) produced approximately 0.30×10⁶ eggs, of which 0.25×10⁶ were fertilized; first-generation broodstock (F1) produced 2.00×10⁶ eggs, of which 1.90×10⁶ were fertilized. Larvae were reared at temperatures of 21.0-24.5℃. The feeding regime consisted of rotifers Artemia, and commercial pellet feed. From 5-8 days after hatching (dah), rotifers collected from high-density incubation tanks were fed to grouper larvae at a density of 10-20 individuals/mL. From 9-30 dah, rotifers collected from low-density incubation tanks were fed to larvae at a density of 10-20 individuals/mL. Newly hatched Artemia were provided from 20-24 dah and enriched Artemia from 25-50 dah. Commercial pellet feed was given starting at 13 dah. The average mouth size in hatchlings was 263.4±3.7 ㎛ at 5 dah, 406.7±21.0 ㎛ at 11 dah, and 856.9±136.6 ㎛ at 21 dah. At 1 dah, larvae had a mean total length of 1.95±0.06 mm. At 66 dah, the mean TL was 4.0 cm. The final number of surviving red spotted grouper larvae was 218,380 fishes.

• 한국수산과학회지
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• 제28권3호
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• pp.316-324
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• 1995

한국산 짱뚱어 Boleophthalmus Pectinirostris의 생태와 분포를 검토하기 위하여 1978년부터 1994년까지 우리나라 서남해 연안 17개 지점에서 표본을 채집하여 소화관 내용물, 초기발생, 체장조성, 그리고 저질, 수온, 염분, 서식공등의 서식환경과 분포지를 검토하였다. 전장 20mm 이상의 저서생활 단계에서 소화관 내용물은 대부분 규조류로서 식물성이었다. 산란기는 5월 하순부터 8원 중순이었고, 산란성기는 6월 중순에서 7월 하순으로 나타났다. 부화 직후 자어의 전장은 3.0-3.4mm로서 이 시기에는 유영생활을 하다가 전장 16mm에 이르면 저서생활을 시작하며, 부화 후 만 2년이 되면 성어로 성장하였다. 본 종은 간조시 평균 4-5시간 노출되는 조간대 연이질$(mud 96\%)$에 분포하는데, 이온이 $16^{\circ}C$ 이상을 유지하는 5월에서 11월까지 이면상에 나타나 활동을 하고, 나머지 기간은 휴지기로서 YL자형의 서식공내에서 동면하였다. 한편 서식공내의 염분은 거의 일정하게 $9-11\%o$를 유지하였다. 국내에서 짱뚱어의 분포지는 서해안과 남해서부 연안의 조간대에 제한 분포하였으나, 간척 매립 등의 생태계 변화로 서식지 및 서식 개체수가 현저히 감소되고 있는 추세이다.