• Journal of Life Science
• /
• v.20 no.12
• /
• pp.1902-1905
• /
• 2010

This study was conducted to increase the efficiency of farming practice in rainbow trout, Oncorhynchus mykiss, by sex reversal and chromosome-set manipulation techniques. Induction of sex-reversed gynogenetic diploid rainbow trout males and mass production of all-female rainbow trout by genetic sex reversal was performed. Phenotypic males in the gynogenetic diploid group were induced successfully by dietary administration of 5 mg of 17 alpha-methyltestosterone per kg diet for 82 days. All females were produced by crossing between normal female and sex-reversed gynogenetic diploid male rainbow trout.

• Journal of Aquaculture
• /
• v.8 no.4
• /
• pp.271-283
• /
• 1995

Blue tilapia, Oreochromis aureus (Steindachner) swim-up fry were fed a ration containing 0, 1, 10, or 60 ppm $17\alpha-Methyltestosterone$ (MT) for 30 days (sex reversal period). Fish that had been fed 0 ppm MT-treated feed during the sex reversal period were subsequently fed rations containing either 0 ppm MT, 10 ppm MT, or 60 ppm MT for the next 39 days (post sex reversal period) : fish that had been fed 60 ppm MT-treated feed during the sex reversal period were subsequently fed rations containing either 0 ppm MT, 10 ppm MT, or 60 ppm MT during the post sex reversal period. One group was fed 1 ppm MT-treated feed, while another group was fed 10 ppm MT-treated feed during both periods. The following growing season (10 months later), the residual effects of MT on weight gain, body composition, and gonosomatic indices (GSI) were evaluated. MT had no residual effect on growth of either sex. Groups that ate MT-treated feed were significantly (P<0.05) larger than those that received no MT during the sex reversal period, because females in the latter group lowered average weight gain. MT had a positive residual effect on body fat content in males, but had a negative effect on body moisture content. MT had a positive residual effect on body moisture content in females. MT had a significant negative effect on male and female GSI at the end of the post sex reversal period. MT consumption during the sex reversal period had a significant negative residual effect on male GSI. MT fed after sexual development (post sex reversal period) did not have a residual effect on male or female CSI.

• Development and Reproduction
• /
• v.25 no.1
• /
• pp.55-57
• /
• 2021

Samples were collected from the subtidal region of Jumunjin on the eastern coast of Korea in July 2020. A total of 338 mussels of shell height (SH) 20.8-149.8 mm were used for sex ratio analysis. The sex ratio (F:M) in the same population of mussel Mytilus coruscus was approximately 1:0.7. The sex ratio according to the class of SH was different. The sex reversal pattern of M. coruscus appears to go from male → female → male → female, and as such is determined to be sequential hermaphrodites.

• Journal of Aquaculture
• /
• v.1 no.1
• /
• pp.53-66
• /
• 1988

Histological study was conducted to determine the initial treatment time and treatment period of hormone for sex reversal in accordance with gonadal development and sexual differentiation in Oreochromis niloticus. The effects of various concentrations and various treatment periods of 17$\alpha$-methyltestosterone (MT) on sex reversal, growth, and condition factor were also evaluated. Paired primodial gonads were formed 9 days after hatching, when germ cells began their gradual multiplication and development into gonial ones. Sex differentiation of gonads either into ovaries or testes became histologically discernible about 20 days after hatching with formation of ovarian cavity and efferent duct. All feed treated with MT at 15 ppm for 10 days or more produced populations of males $95\%$ or above. All male populations were produced at 15 ppm MT for 40 days, and 30 ppm for 30 and 40 days. Growth of hormone-treated-fish was faster than that of untreated ones and the condition factor of hormone-treated-fish was greater than that of untreated ones 77 days after hatching.

• Journal of Aquaculture
• /
• v.9 no.3
• /
• pp.279-285
• /
• 1996

The effects of various concentrations of $17{\beta}-methyltestosterone$ (MT) or $17{\beta}-estradiol\;(E_2)$ on sex reversal, survival and growth rates of olive flounder, Paralichthys olivaceus were investigated. MT and $E_2$ were treated to juvenile flounder for 60 days from 30 (total length : 14.5 mm) to 90 (TL : $10.41\~11.17$ mm) days after hatching. Fish were treated with 0, 1, 10 and 100 ppb of MT or $E_2$ in the rearing water for 2 hours per day. At the time of 200 days after hatching, fish were sampled to examine sex ratio. One hundred pub of MT produced $100\%$ male, however 1 and 10 ppm MT produced 72.5 and $87.2\%$ males. One, 10 and 100 ppb of $E_2$ produced 75.5, 91.9 and $97.2\%$ females, respectively. Survival and growth rates of each experimental group at the end treatment were not significantly different from those of the control (P>0.05).

• Development and Reproduction
• /
• v.14 no.1
• /
• pp.1-5
• /
• 2010

We investigated the androgenic effects of 11-ketotestosterone (11-KT) on gonadal sex reversal and spermatogenesis in honeycomb grouper Epinephelus merra by method of gonadal biopsy. 11-KT was injected intramuscularly at a concentration of 1 and $10{\mu}g$ body weight. The proportion of cross sectional area of the gonad occupied by each germ cell type was measured and compared pre- and post-injection group. During the sex change phase, the distribution ratio of oocytes was decreased in all fish of 11-KT treatment group while the distribution ratio of spermatocytes was increased than pre-injection group. In male phase, all fish of 11-KT treatment group shown the increased distribution ratio of spermatocytes, but the distribution ratio of spermatozoa was decreased than pre-injection group. The present results suggest that 11-KT can stimulate degeneration of oocytes, proliferation of spermatocytes and spermiation in honeycomb grouper.

• Journal of Chest Surgery
• /
• v.53 no.5
• /
• pp.258-262
• /
• 2020

Background: The aim of this study was to evaluate risk factors associated with difficult heparin reversal by protamine after cardiopulmonary bypass. Methods: Data from 120 consecutive patients who underwent open heart surgery from 2009 to 2017 were retrospectively reviewed. Patients were divided into 2 groups: (1) those in whom complete heparin reversal was achieved after a single infusion of protamine (group A, n=89); and (2) those who required more protamine for heparin reversal (group B, n=31). Results: Female sex, prolonged bypass time (>200 min), long aortic cross-clamping time (>120 min), and a lowest rectal temperature <26℃ were significant predictors of difficult heparin reversal. Larger amounts of fresh frozen plasma and platelet concentrate were transfused in group B than in group A. Conclusion: Surgeons' efforts to reduce operative time and avoid deep hypothermia may be helpful for increasing the likelihood of easy heparin reversal, especially in female patients.

• Journal of Genetic Medicine
• /
• v.13 no.2
• /
• pp.78-88
• /
• 2016

Purpose: To identify the clinical characteristics of SRY-negative male patients and genes related to male sex reversal, we performed a retrospective study using cases of 46,XX testicular disorders of sex development with a review of the literature. Materials and Methods:SRY-negative cases of 46,XX testicular disorders of sex development referred for cytogenetic analysis from 1983 to 2013 were examined using clinical findings, seminal analyses, basal hormone profiles, conventional cytogenetic analysis and polymerase chain reaction. Results: Chromosome analysis of cultured peripheral blood cells of 8,386 individuals found 19 cases (0.23%) with 46,XX testicular disorders of sex development. The SRY gene was confirmed to be absent in three of these 19 cases (15.8%). Conclusion: We report three rare cases of SRY-negative 46,XX testicular disorders of sex development. Genes on autosomes and the X chromosome that may have a role in sex determination were deduced through a literature review. These genes, through differences in gene dosage variation, may have a role in sex reversal in the absence of SRY.

• Journal of Life Science
• /
• v.20 no.11
• /
• pp.1634-1639
• /
• 2010

This study was conducted to increase the efficiency of farming practice in rainbow trout, Oncorhynchus mykiss, by sex reversal and chromosome-set manipulation techniques. To obtain phenotypic males, hormonal sex reversal was carried out using an exogenous hormone treatment method. 5 mg of 17 alpha-methyltestosterone per kg diet was supplied for 82 days after first feeding at $10^{\circ}C$ and $13^{\circ}C$. More than 93% of the male population was produced by this method and growth of hormone-treated fish at $13^{\circ}C$ was faster than that of untreated bi-sexual groups. Induced diploid gynogenesis was carried out using artificial insemination of UV-irradiated sperm into haploid eggs. Based on the appearance of the rate of haploid syndrome and survival of embryo, a UV ray dose of at least $3,600\;erg/cm^2$ was required to inactivate rainbow trout sperm genetically. Haploid embryos were restored to diploid by blocking the extrusion of the second polar body using heat shock treatment at $28^{\circ}C$ for 20 min, 10 min post insemination. Gynogenetic diploid sex ratios were confirmed after maturation of the fish erythrocyte measurements and chromosome counts.

• Fisheries and Aquatic Sciences
• /
• v.14 no.2
• /
• pp.148-160
• /
• 2011

Thirty-one gross abnormalities that have been observed in tilapia are described: 10 fin, five eye, five jaw, four body shape, three head, two yolk sac, one operculum, and conjoined twins. Twenty-one have been described in published papers; the others were obtained from a survey. Breeding experiments revealed that three were heritable, while six were not heritable. Five could be caused by a bacterial infection, and one could be produced by a fungus. Four deformities were in offspring of males that had been injected with methyl methane sulphonate. Three were produced when sperm was treated with methyl methane sulphonate. Six were observed during sex reversal studies, and one was found following heat shock of fertilized eggs. Three were observed in polluted river water. The cause of other deformities is not known.