• 한국양식학회지
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• 제8권3호
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• pp.183-193
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• 1995

청틸라피아 (Oreochromis aureus)의 자어에 0, 1, 10, 60 ppm의 $17\alpha-methyltestosterone$(MT)을 30 일간 사료에 섞어 먹인 후 다음 57 일간을 0 ppm을 먹인 그룹은 다시 세그룹으로 나누어 0 ppm MT (0-0), 10 ppm MT (0-10), 및 60 ppm MT (0-60)을 먹였고, 60 ppm 을 먹인 그룹은 다시 3 그룹으로 나누어 0 ppm MT (60-0), 10 ppm MT (60-10), 및 60 ppm MT (60-60)을 먹였으며, 초기 30 일간 1 ppm과 10 ppm MT를 먹인 것은 계속해서 1과 10 ppm을 먹여서 체조성과 생식소 중량지수에 미치는 영향을 조사하였다. 초기 30 일간 어체의 조단백과 조지방은 MT 농도와 역상관 관계를 보였고, 수분 함량은 순상관 관계를 보였다. 후기 57 일간에 먹인 MT는 초기 30 일간 먹인 MT 보다도 숫컷의 체조성에 더 큰 영향을 미쳤다. 사료 중의 MT는 초기 30 일간이나 후기 57 일간 모두 숫컷의 생식소 중량지수에 나쁜 영향을 보인 반면에, 암컷의 경우에는 후기 57 일간에 사료 중의 MT 양이 생식소 중량지수에 나쁜 영향을 나타내었다.

• 한국발생생물학회지:발생과생식
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• 제16권4호
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• pp.385-388
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• 2012

The sex ratio (F:M) in the same population of oyster, Crassostrea gigas at the commencement of the study (2007) was 1:1.0, but changed to 1:2.8 by the end of the study (2008). The sex reversal rate in two-year-old oysters was 40.2%. Specifically, female to male sex reversal rate was 66.1%, which is higher than the male to female sex reversal rate of 21.1%. The sex reversal pattern of C. gigas appears to go from male ${\Rightarrow}$ female ${\Rightarrow}$ male, and as such is determined to be rhythmical hermaphroditism.

• 한국발생생물학회지:발생과생식
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• 제18권2호
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• pp.73-78
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• 2014

This study attempts to propose the possibility of the sex reversal in Sinonovacula constricta and Gomphina veneriformis by confirming the changes in the sex ratio with the shell length in the same population level. For analysis of sex ratio, 100 individuals of S. constricta (SL 26.5-95.0 mm) and 2385 individuals of G. veneriformis (SL 15.1-60.1 mm) were used. Sex was analyzed histologically. Both species displayed the tendency of increase in the female proportion with increase in shell length. In this study, changes in the sex ratio in accordance with the growth of S. constricta and G. veneriformis are determined to be indirect evidence that signifies their sex reversal.

• 한국발생생물학회지:발생과생식
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• 제16권3호
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• pp.177-183
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• 2012

This study attempts to propose the possibility of the sex reversal in Tegillarca granosa and Ruditapes philippinarum by confirming the changes in the sex ratio with the shell length (SL) in the same population level. For analysis of sex ratio with SL, 1500 individuals of T. granosa (SL 10.1-45.0 mm) and 712 individuals of R. philippinarum (SL 15.1-70.0 mm) were used. Sex was analyzed histologically. The average sex ratios (F:M) of T. granosa and R. philippinarum were 1:1.22 and 1:0.96, respectively. However, sex ratio was found to differ when the clams were divided into groups according to SL in 5.0 mm intervals. Both species displayed the tendency of increase in the proportion of female with increase in SL. In this study, changes in the sex ratio in accordance with the growth of T. granosa and R. philippinarum are determined to be indirect evidence that signifies their sex reversal.

• 한국패류학회지
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• 제31권4호
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• pp.315-322
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• 2015

이매패류의 성은 자웅이체와 자웅동체로 구분되며, 자웅이체는 동시자웅동체와 비동시자웅동체로 나누어진다. 비동시자웅동체는 계절에 따른 성의 전환을 의미한다. 일반적으로 자웅이체 이매패류의 경우 형태학적 성으로 표현되는 암, 수는 개체의 생활사 가운데 일정한 한 시기에 국한된 것이다. 개체의 성을 정확히 확인하기 위해서는 성을 표지한 후, 생활사 동안 성의 변화를 연속적으로 추적해야 한다. 이매패류에서 성전환과 비동시자웅동체는 굴과, 가리비과, 백합과 및 돌조개과 등의 이매패류에서 보고되고 있다. 이들 연구의 대부분은 동일 개체군에서 연령에 따른 성비의 변화를 증거로 이러한 결론에 도달하게 되었다. 비동시자웅동체 이매패류에서 성의 변화는 보통 방란, 방정 후 생식소의 비활성기에 일어난다. 이매패류에서 성결정과 성의 변화에는 유전적 요인과 환경적 요인 두 가지가 관여하지만, 이에 관한 이들의 영향에 관해서는 세부적인 연구가 필요하다.

• 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

• 한국양식학회지
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• 제9권1호
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• pp.19-23
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• 1996

Hormonal induction of sex reversal was examined by using sex steroid hormones in serranid fish, Epinephelus septemfasciatus. Young fish were collected from the coastal area of Cheju Island, and reared for 2 years before fish were used for the experiments. Without any hormonal treatment, gonads of fish ($1,000\~2,800$ g in body weight) were occupied by oocytes of the perinucleolus stage and bundles of protogonial cells in the area of germinal epithelium. When the induction of sex reversal was attempted by daily oral administration of $17\alpha$-methyltestosterone (0.5 mg/kg fish) for 90 days, active spermatogenesis was induced, and spermatogonia and spermatocytes and spermatids were appeared in all gonads we examined. However, after daily, oral treatment of $17\beta$-estradiol (0.5 mg/kg fish) to. 50 days with the following injection of human chorionic gonadotrophin ($1,000\~1,500$ IU/kg fish) mature oocytes were not induced in fish gonad.

• 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)

• 한국발생생물학회지:발생과생식
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• 제17권2호
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• pp.79-85
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• 2013

To understand the sex reversal characteristics in the longtooth grouper (Epinephelus bruneus), this study examined the sex reversal and artificial masculinization of wild caught E. bruneus reared in indoor rearing tank after a 17${\alpha}$-methyltestosterone injection. To domesticate a broodstock, 64 wild caught E. bruneus, between 47.0 to 110.0 cm in total length and from 1.5 to 21.4 kg in body weight, were reared in indoor rearing tank (4.0 to 5.0 m wide, and 2.5 to 3.0 m depth) for four years. Seven specimens showed sex reversal from female to male during indoor rearing condition, whose total length and body weights were from 63.0 to 99.0 cm and from 4.4 to 13.2 kg, respectively. After inducing artificial masculinization in 14 female E. bruneus with a 17${\alpha}$-methyltestosterone (2.0 mg/kg BW) implants for 3 years, spermiation occurred in 9 specimens (total length: 54.0 to 68.0 cm, body weight: 2.3 to 4.3 kg). Among the female to male sex reversals, two specimens returned back to being female, whose body weights were 2.8 kg (initially 2.6 kg) and 2.7 kg (initially 2.3 kg). Therefore, this study suggested that E. bruneus (> 3.0 kg) was more effective in masculinizing by 17${\alpha}$-methyltestosterone implants.

• 한국임상수의학회지
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• 제25권3호
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• pp.221-223
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• 2008

SRY gene is normally responsible for testis induction, yet testis development can occur in the absence of SRY. In here, we analyzed the SRY-negative sex reversal in cocker spaniel, at 1.5 year-old. The attacked dog was suffered from enlarged clitoris, and resulted in disorder of urination. By surgically approach, enlarged clitoris and one testis, which are apparently seen, are removed. Additionally, thorough the abdomen surgery, uterus and ovary-like mass were removed. The dog had XX, chromosome, showed negative for SRY-gene, and the mass had the ovary-testis structure. In other words, based on the macroscopic, cytogenic, and histological study, we can diagnose the cocker spaniel as SRY-negative sex reversal.