• 한국발생생물학회:학술대회논문집
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• 한국발생생물학회 2003년도 제3회 국제심포지움 및 학술대회
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• pp.76-76
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• 2003

Eleven wrasse species inhabit the coastal waters of Jeju Island, Korea. They are the target of leisure fishing and are considered good eating. We investigated the distribution of standard length (SL) by sex of wrasse in Jeju coastal waters for Halichores poecilopterus, H. tenuispinis, Pseudolabrus japonicus, and Pteragogus flagellifera. A cross-section of the ovary showed the ovarian cavity and ovarian lamellae containing oocytes. A cross-section of the testis showed many lobules containing spermatogonia and spermatocytes. A cross-section of a gonad undergoing sex reversal showed the regression or reduction of oocytes and some spermatocytes located in the ovarian lamellae. A cross-section of a sex-reversed testis showed the primary structure of the ovary, with spermatocytes distributed in the epithelium of the lamellae, and reformed seminiferous ducts in the basement lamellae. (중략)

• 한국수정란이식학회:학술대회논문집
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• 한국수정란이식학회 2003년도 제3회 발생공학 국제심포지움 및 학술대회
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• pp.76-76
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• 2003

• 한국발생생물학회:학술대회논문집
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• 한국발생생물학회 2003년도 제3회 국제심포지움 및 학술대회
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• pp.64-64
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• 2003

The sex differentiation of fishes occurs under the control of genetic and various environmental factors. DM-domain containing genes are novel zinc finger transcription factors and play key roles in sex determination. In order to isolate the wrasse DMRT (wDMRT) cDNA from the protogynous wrasse (Halichoeres tenuispinnis), the wrasse testis cDNA library was screened using the $^{32}$ P-labeled PCR products, which were amplified with the degenerate primers from conserved DM-domain regions of several DMRT genes. Among a few positives obtained through screening, the full length wDMRT cDNA of 2.9kb size encoding a predicted 300 amino acid residues was isolated. The sequence analysis exhibited 60%, 43% sequence identity with rainbow trout and tilapia DMRT1, respectively. RT-PCR assay showed that wDMRT was expressed specifically in male testis. Also, wDMRT gene was strongly expressed in May during reproductive season, when the reproductivity of wrasse is most active. This results suggested that wDMRT gene function in testis differentiation The conserved DM-domain regions were amplified using PCR from DMRT genes of several species among Labridae, and their sequences were determined. The sequence of DM-domain region of Halichoeres. tenuispinis was identical to those of Pseudolabrus japonicus, Pteragogus flagellifera, and showed 94% identity with that of Halichoeres poecioptrerus.

• 수산해양교육연구
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• 제25권6호
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• pp.1381-1388
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• 2013

In order to improve the availability of underwater sound by the fundamental data on the hearing ability, the auditory thresholds for the bambooleaf wrasse pseudolabrus japonicus were determined at 80Hz, 100Hz, 200Hz, 300Hz, 500Hz and 800Hz by heartbeat conditioning method using pure tones coupled with a delayed electric shock. The audible range of the bambooleaf wrasse extended from 80Hz to 800Hz with the best sensitivity around 100Hz and 200Hz. In addition, the auditory thresholds over 300Hz increased rapidly. The mean auditory thresholds of the bambooleaf wrasse at the test frequencies, 80Hz, 100Hz, 200Hz, 300Hz, 500Hz and 800Hz were 100dB, 95.1dB, 94.8dB, 109dB, 121dB and 125dB, respectively. Auditory critical ratios for the bambooleaf wrasse were measured using masking stimuli with the spectrum level range of about 70, 74, 78dB (0dB re $1{\mu}Pa/\sqrt{Hz}$). According to white noise level, the auditory thresholds increased as compared with thresholds in a quiet background noise. The Auditory masking by the white noise spectrum level was stared over about 60dB within 80~300Hz. Critical ratios to be measured at frequencies from 80Hz to 300Hz were minimum 33dB and maximum 39dB.

• 한국어업기술학회:학술대회논문집
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• 한국어업기술학회 2003년도 춘계 수산관련학회 공동학술대회발표요지집
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• pp.331-332
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• 2003

Protogyny is known in 14 families of fishes, 11 of which inhabit coral reef areas. The wrasses (Labridae) comprise a large and well-known family of coral reef fishes that exhibit sequential hermaphroditism. The purpose of the present investigation was to examine the allomeoic growth patterns of several morphometric characteristics, including those used commonly to distinguish sexes of cocktail wrasse, pteragogus aurigarius (Richardson) and to assess their effectiveness in discriminating between males and females. (omitted)

• 수산해양기술연구
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• 제50권4호
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• pp.427-434
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• 2014

Although ex situ target strength (TS) measurements using dual- and split-beam systems have become the primary approach of estimating fish abundance, theoretical model estimation is a powerful tool for verifying the measurements, as well as for providing values when making direct measurements is difficult. TS values for 20 samples of live bambooleaf wrasse (Pseudolabrus japonicus) whose target length (TL) ranged between 13.7 and 21.3 cm were estimated theoretically using the Kirchhoff-ray mode model, and the TS values for 18 live fish samples were additionally measured at ${\sim}0^{\circ}$ tilt angle to the swimming aspect using a tethered method at a frequency of 120 kHz to verify the theoretical values. The digitizing intervals used to extract the fish body and swim bladder morphology in the X-ray photographs significantly affected the calculated TS patterns, but variations based on the speed of sound and density ratio values for the general range of fish flesh were relatively small (within 1 dB). Close agreement was observed between the measured and theoretical TS values, and the correlation between the average TS and body length of the fish could be calculated accurately as <$TS_{120kHz}$>= 20logTL (cm) -71.6 using the theoretical method.

• 한국수정란이식학회:학술대회논문집
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• 한국수정란이식학회 2003년도 제3회 발생공학 국제심포지움 및 학술대회
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• pp.64-64
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• 2003

• 한국어류학회지
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• 제11권1호
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• pp.42-45
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• 1999

놀래기과 어류 Cheilinus bimachulatus의 산란 행동을 조사하기 위해 1997년 7월과 8월 두달에 걸쳐 일본(日本) 녹아도(鹿兒島)의 침기(枕崎)에서 수중 관찰 및 video 촬영을 하였다. C. bimaculatus의 mating system은 haremic이었다. 본 종의 수컷은 수중의 커다란 바위 또는 연산호의 덤불을 중심으로 짝짓기를 위한 세력권을 형성하였고 자신의 세력권 내에 2~3마리의 암컷을 거느렸다. 암컷은 수컷의 세력권 안에서 작은 바위 또는 연산호의 덤불을 중심으로 작은 세력권을 형성하였다. 오후 3시부터 3시30분 사이에 수컷은 자기 세력권 내의 암컷과 차례차례 산란하였다. 방란, 방정을 하기 전에 특유의 산란 행동을 하였다. 본 연구에서 streaking, sneaking 및 group spawning은 관찰되지 않았다.

• 한국동물학회:학술대회논문집
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• 한국동물학회 2003년도 한국생물과학협회 학술발표대회
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• pp.210.3-210
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• 2003

No Abstract, See Full Text

• 한국동물학회:학술대회논문집
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• 한국동물학회 2003년도 한국생물과학협회 학술발표대회
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• pp.197.3-197
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• 2003

No Abstract, See Full Text