• Title/Summary/Keyword: 17-estradiol

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Single Nucleotide Polymorphisms of the GnRHR Gene Associated with Reproductive Traits of Japanese Flounder (Paralichthys olivaceus)

  • He, Feng;Wen, Hai-Shen;Li, Ji-Fang;Yu, Da-Hui;Ma, Rui-Qin;Shi, Dan;Mu, Wei-Jie;Zhang, Yuan-Qing;Hu, Jian;Liu, Miao;Han, Wei-Guo;Zhang, Jia-Nan;Wang, Qing-Qing;Yuan, Yu-Ren;Liu, Qun
    • Asian-Australasian Journal of Animal Sciences
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    • v.24 no.4
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    • pp.463-470
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    • 2011
  • Gonadotropin-releasing hormone receptor (GnRHR) gene is expressed at the anterior pituitary gland and plays a key role in gonad development. This study aimed to investigate molecular genetic characteristics of the GnRHR gene and elucidate the effects of single nucleotide polymorphisms (SNPs) of GnRHR gene on sex steroid level in Japanese flounder (Paralichthys olivaceus). We used polymerase chain reaction single-strand conformation polymorphism (PCR-SSCP) and sequencing of the GnRHR gene in 75 individuals. We identified three SNPs in the GnRHR gene: P1 locus (C759A and C830T) in the coding region of exon2 which were both linked together and P2 locus (G984T) in the coding region of exon3, which added a new transcript factor (ADR1) and a new methylation site (CG). Only C830T of P1 leads to amino acid changes Thr266Ile. Statistical analysis showed that P1 was significantly associated with $17{\beta}$-estradiol ($E_2$) level (p<0.01) and gonadosomatic index (GSI) (p<0.05). Individuals with genotype BB of P1 had significantly higher serum $E_2$ levels (p<0.01) and GSI (p<0.05) than those of genotype AA or AB. Another SNP, P2, synonymous mutation, was significantly associated with GSI (p<0.05). Individuals with genotype AB of P2 had significantly higher GSI (p<0.05) than that of genotype AA. In addition, there was a significant association between one diplotype based on three SNPs and reproductive traits. The genetic effects for both serum $E_2$ level and GSI of diplotype D4 were super diplotypes (p<0.05). These results suggest that the SNPs in Japanese Flounder GnRHR are associated with $E_2$ level and GSI.

Performance differences of Rhode Island Red, Bashang Long-tail Chicken, and their reciprocal crossbreds under natural cold stress

  • Xie, Shanshan;Yang, Xukai;Gao, Yahui;Jiao, Wenjie;Li, Xinghua;Li, Yajie;Ning, Zhonghua
    • Asian-Australasian Journal of Animal Sciences
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    • v.30 no.10
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    • pp.1507-1514
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    • 2017
  • Objective: The Bashang Long-tail chicken (BS), an indigenous Chinese breed, is considered cold tolerant. We selected BS, the Rhode Island Red (RIR), and their reciprocal crossbreds for the present study. The objectives were: i) to validate whether BS is cold tolerant and whether egg production and cold tolerance of crossbreds could be improved; and ii) to determine the physiological characteristics that underlie cold tolerance and favorable egg production performance in cold environments. Methods: A total of 916 chickens were reared in warm and natural cold environments (daily mean ambient temperature varied from $7.4^{\circ}C$ to $26.5^{\circ}C$ in the warm environment and from $-17.5^{\circ}C$ to $27.0^{\circ}C$ in the cold environment). To investigate their adaptability to the cold environment, the egg production performance and body weight were monitored and compared between breeds and environments. The cloacal temperature and serum biochemical parameters were monitored to reveal the physiological characteristics underlie cold tolerance and favorable egg production performance in the cold environment. Results: The warm environment experiment showed that RIR had the highest egg production performance, and that the reciprocal crossbreds had a higher egg production performance than BS. While in the cold environment RIR had the lowest egg production performance, and the reciprocal crossbreds had a higher egg production performance than BS. In the cold environment BS and reciprocal crossbreds had higher triiodothyronine, tetraiodothyronine levels than RIR. At 35 and 39 wk of age, when the ambient temperature was extremely low (varied from $-20^{\circ}C$ to $0^{\circ}C$), serum glucose, follicle-stimulating hormone, luteinizing hormone, estradiol of BS and crossbreds were higher than RIR. Conclusion: Bashang Long-tail chicken has a favorable cold tolerance ability. Crossbreeding with RIR and BS is an effective way to develop cold tolerant chickens with improved egg production performance.

Estrogenic Activity, and Developmental Toxicity Studies of Pyrethroid Insecticides

  • Kim, Soon-Sun;Rhee, Gyu-Seek;Lee, Rhee-Da;Kwack, Seung-Jun;Lim, Kwon-Jo;Yhun, Hyo-Jung;Park, Kui-Lea
    • Proceedings of the Korea Society of Environmental Toocicology Conference
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    • 2003.10a
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    • pp.57-69
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    • 2003
  • It is well known that many pesticides possess hormonal activity, and affect the developments of wildlife and mammals including human. Currently, pyrethroid insecticides are in worldwide use to control in and outdoor pests, providing potential far environmental exposure. Hormonal activities of these pyrethroid insecticides, however, have been little studied, and the developmental effects of them were no reported. Therefore, we firstly examined the potential estrogenic activities of some pyrethroid insecticides (permethrin, cypermethrin, tetramethrin, deltamethrin, sumithrin, fenvalerate and bioallethrin) by immature rat uterotrophic assay, luciferase reporter gene assay and Calbindin-D$\sub$9k/ (CaBP-9k) gene expression assay. Uterine wet weights were increased by permethrin and the permethrin-induced weights were inhibited by ICI 182780 in the uterolrophic assay. On the other hand tetramethrin significantly reduced uterine and vaginal wet weights, and also inhibited the E2-induced weight increases at all doses tested. Cypermethrin and sumithrin had a tendency to increase uterine weights, although not statistically significant. Permethrin and cypermethrin dose-dependently increased the luciferase activity in reporter gene assay. Northern blot analysis showed that permethrin induced CaBP-9k mRNA expression whereas tetramethrin inhibted. Subsequent studies were conducted to investigate the possible developmental effects of four pyrethroid insecricides (permethrin, cypermethrin, sumithrin and teramethrin). Either diethlbestrol (DES) or 17${\beta}$ -estradiol (E2) was used as a reference control in this study. Pyrethroid insecticides were administered to Sprague Dawley rats via subcutaneous injection at 6 to 18 days of gestation or 1 to 5 days after birth. In utero treatment of permethrin (10mg/kg/day) in female rat resulted in significant increases in uterine and ovarian weights while significant decreases in serum E2 concentration, uterine and ovarian ER${\alpha}$ mRNA levels. Sumithrin and permethrin led to acceleration in vaginal opening of female rat, while delay in preputial separation of male after neonatal treatment. Anogenital distances of PND 18 were significantly reduced in sumthrin-treated, and permerhrin-treated male rats after neonatal treatment. All the pyrethroid insecticides tested caused significant increases in uterine weights on PND 18, while significant reductions in the first diestrus phase when neonataly treated. In addition, exposure to pyrethroids in neonatal period led to significant reduction in relative brain weight in female rat on PND 18, but its weight was recovered in diestrus phase. In summary, Our experimental data demonstrate the possibilities of developmental effects of pyrethroid insecticides via estrogenic or antiestrogenic activity.

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Effects of established cell lines on bovine embryo development during in vitro culture (계대세포를 이용한 소 수정란의 체외배양 체계에 관한 연구)

  • Joo, Suk-chun;Lee, Byeong-chun;Lee, Won-yu;Choi, Yun-seok;Hwang, Woo-suk
    • Korean Journal of Veterinary Research
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    • v.37 no.3
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    • pp.647-659
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    • 1997
  • To overcome the difficulties of collecting and culture of primary cell from genital tract on embryonic development, the present study was carried out to investigate the critical effect of cell lines, such as BRL and Vero cell and its conditioned medium on the development of early Korean native cattle embryos in vitro. Oocytes collected from slaughterhouse ovaries were matured in TCM199 containing FSH, estradiol-$17{\beta}$ and FBS with granulosa cell monolayer for 24 hours and then fertilized in vitro using frozen-thawed, heparin-treated spermatozoa in TALP for 30 hours. And then early embryos (1-2cell) were cultured in TCM199 containing 10% FBS with BOEC, Granulosa, BRL, Vera cell monolayers and conditioned medium for 2~3 days. Development to morulae and blastocysts were recorded, also examined the number of blastomeres presented a valuable parameter for the evaluation of embryonic development. The early cleavage rates of in vitro fertilized embryos co-cultured, there was no differences between primary cell and cell lines(p<0.05). The rate of development to the later stage, coculture of BRL cell was significantly higher than that of the primary cell(p<0.05). The rates of development to morula and blastocyst were significantly higher in vero cell than BRL, Granulosa, Oviduct epithelial cell conditioned medium. In the result of effect of serum on development of early bovine embryos, the use of media containing serum were significantly higher than the use of not containing one on development of early and later stage of embryos. The result of number of blastomeres in blastocysts, there is no differences between primary cell and cell lines. The blastocysts from coculture were higher than from conditioned medium in blastomere cells. In summary, these experments have proved that the culture system in TCM199 with BRL, Vero cell monolayers is effective on in vitro development of early bovine embryos, In addition, it is effective to development of bovine embryos that containing serum in conditioned medium, or in co-culture rather than in conditioned medium alone. The use of cell lines opponent to primary cells is effective in bovine embryo culture.

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Studies on the Factors Affecting the IN-Vitro Maturation and Fertilization of Bovine Follicular Oocytes (소 난포란의 체외성숙과 체외수정에 영향을 미치는 요인에 관한 연구)

  • 김상근;이만휘
    • Journal of Embryo Transfer
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    • v.7 no.1
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    • pp.1-12
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    • 1992
  • 본 연구는 소의 난포란의 체외성숙과 체외수정에 영향을 미치는 요인을 구명하기 위하여 미숙 난포란을 채취하여 형태적 분류를 통해 우수한 란을 공시한 후 난포의 크기, 정액의 형태, 수정능득법, 혈청, 호르몬, 난포액, 난구세포등을 첨가한 TCM-199 배양액에서 배양하면서 체외성숙 및 수정율을 조사하였는 바 그 결과는 다음과 같다. 1. 소 난포란을 채취하여 배양을 통해 형태적 분류를 했을때 A형란은 61.4%, B형란은 12.1%, C형란은 19.2%, D형란은 4.2%였으며 발생중지 또는 퇴화란은 3.0%였다. 또한 A, B, C형란을 배양액에 배양했을때 난포란의 체외성숙율은 각각 89.1%, 78.0%, 52.6%였으며, 수정율은 각각 78.1%, 66.1%, 33.3%였다. 2. 소 난포의 크기를 1-2mm, 3-5mm 및 5mm이상으로 분류하여 채취한 난포란의 수는 각각 67개, 98개, 63개 였으며, 이를 TCM-199 배양액에서 배양했을때의 체외성숙 및 수정율은 각각 56.7%와 44.8%, 82.5%, 72.4%와 46.0%와 28.6%였다. 3. 소 난포란의 체외수정에 있어서 정소상체 미부정자, 희택정액 및 동결정액을 이용하여 매정하였을때 체외수정율과 분할율은 각각 63.3%, 73.3%, 70.0%와 32.7%, 37.8%, 38.3%였다. 4. 소 난포란의 체외수정에 있어서 m-KRB 처리법, HIS처리법, Ca-IA처리법, BFF처리법 및 heparin처리법으로 각각 수정능획득을 유기하였을때 체외성숙 및 분할율은 각각 53.1%, 28.1%, 33.9%와 17.7%, 50.8%와 26.2%, 48.1%와 22.8% 및 58.8%와 32.8%로서 heparin 처리법이 가장 높았다. 5. 소 난포란의 체외성숙과 수정에 있어서 각 농도의 우태아혈청과 FSH, HCG, $\beta$-estradiol을 첨가한 TCM-199배양액에서 배양했을때의 체외성숙 및 수정율은 각각 76.0-82.3%와 26.2-70.0%로서 무첨가에 비해 첨가가 높았다. 6. 발정우혈청 및 우태아혈청 5-20%를 첨가한 배양액에서 배양했을때의 체외성숙율은 각각 71.7-76.9%, 74.0-80.6%였으며 체외수정율은 51.9-58%와 26.2-30.0%로서, 체외수정율의 경우 발정우혈청의 첨가가 우태아혈청의 첨가에 비해 높았다. 7. 난포액20-30%를 첨가한 배양액에서 배양했을때의 난포란의 체외성숙율은 각각 68.0%와 64.6%, 수정율은 각각59.6%와 60.4%로서 난포액10%, 50%를 첨가한 배양액에서 배양시의 체외성숙율과 수정율에 비해 높았다. 8. 1$\times$10 6 /ml의 난구세포를 첨가한 배양액에서 배양했을때의 난포란의 체외성숙율과 수정율은 각각 76.5%와 61.7%로서 FCS 10%와 1$\times$10 4 -10 5/ml 와 1 $\times$10 8/ml난구세포를 첨가한 배양액에서 배양시의 체외성숙율과 수정율에 비해 높았다.

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Hormonal Analysis of Female Transgender Patients Performed Gender Reassignment Operation (여성 성전환수술을 받은 환자의 호르몬 정량분석)

  • Park, Jung Min;Kwon, Yong Seok;Lee, Keun Cheol;Kim, Seok Kwun;Kwak, Hyun;Kim, Sang Beom
    • Archives of Plastic Surgery
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    • v.32 no.6
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    • pp.699-705
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    • 2005
  • Transgender is the severe type of gender identity disorder. The prevalence rate of transgender is reported to occur to about 1 out of 50,000 men, and about 1 out of 10,000 women. As for Korea, it is estimated to have about 1400 transgender patients. Lately, not only the numbers of them are increasing but also they are influencing our society increasingly. As for female transgender patients, they take female hormone for a long term before and even after the operation to maintain their physical identity of female. We have analyzed insulin like growth factor-1(IGF-1), insulin like growth factor protein binding-3(IGFBP-3), female hormone, male hormone and thyroid hormone in female transgender patients who have undergone the gender reassignment operation. We examined the changes of hormone level due to having female hormone steadily, and also examined how the steady use of the hormone could affect body organs. As for IGF-1, it showed significantly low in the female transgender group compared to control ($319.30{\pm}37.4$ vs $539{\pm}55.0$, p<0.05). As for IGFBP-3, there was no significant difference ($2859{\pm}200.3$ vs $2607{\pm}262.5$, p>0.05). As for female hormone, there was no significant differences in FSH($13.42{\pm}13.8$ vs $8.95{\pm}3.5$, p>0.05), estradiol($104.41{\pm}97.1$ vs $121.68{\pm}60.2$, p>0.05), and LH($7.62{\pm}5.6$ vs $7.4{\pm}3.3$, p>0.05). Even in comparison of testosterone, there was no significant differences($0.23{\pm}0.09$ vs $0.33{\pm}1.33$, p>0.05). As for thyroid hormone, there was no significant differences in TSH and free T4($1.34{\pm}0.94$ vs $1.71{\pm}0.12$, $1.4{\pm}0.37$ vs $1.46{\pm}0.17$, p>0.05). Therefore, this study concludes that apart from the decreased level of IGF-1, the possible endocrine side-effect problem due to female hormone seems to be low because there was no differences of female, male, and thyroid hormone level compared with normal female. Further study will be required in metabolic change including bone metabolism occurred by decrease level of IGF-I.

Alteraation of Gonadotropin-releasing Hormone and Luteinizing Hormone ${\beta}$-Subunit mRNA Levels in Neonatally Estrogenized Female Rats

  • Song, Eun-Sup;Kang, Sang-Soo;Cho, Se-Hyung;Choe, Young S.;Geum, Dong-Ho;Choi, Don-Chan;Kim, Kyung-Jin
    • Animal cells and systems
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    • v.1 no.4
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    • pp.595-602
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    • 1997
  • Treatment of newborn female rats with gonadal steroids induces permanent sterility in adulthood. We investigated the alteration in expression patterns of gonadotropin-releasing hormone (GnRH) and luteinizing hormone (LH) in neonatally estrogenized sterile rats (ESR). Newborn female rats received daily injections of 17${\beta}$-estradiol (E, 10 ${\mu}$g) from the day of birth (day 1) to postnatal day 5. Controls were subjected to vehicles over the same period. All animals were sacrificed on week 7 after birth. Hypothalamic GnRH mANA levels were markedly higher in all ESR than in controls, while hypothalamic GnRH contents in ESR increased in proportion to the frequency of daily administration of E. However, both pituitary LH6 mRNA and serum LH levels were inversely decreased by the same treatment. The data indicate that neonatal exposure of E equally elevates the expression of GnRH gene, but reduces the secretion of GnRH, accordingly leading to attenuation of LH6 gene expression and circulating LH levels. The temporal effect of E and/or progesterone (P) on GnRH and LH6 mRNA levels was also examined in ESR. Newborn female rats were daily injected with E (10 ${\mu}$g) or vehicle for five successive days from day 1 and ovariectomized at week 5. They were implanted with E (235 ${\mu}$g/ml) two days prior to week 7, injected with P (1 mg) 42 h later, and sacrificed 7 h after P administration. In ovariectomized controls, hypothalamic GnRH mRNA levels were dropped to half by treatment of E and restored by subsequent treatment of P. The negative feedback action of E on GnRH mRNA levels observed in ovariectomized rats was completely blocked by neonatal exposure of E. The change in pituitary LH mRNA levels was similar to that in hypothalamic GnRH mRNA levels. Taken together, the results suggest that neonatal treatment of E alters the synthesis and release of GnRH in adulthood and furthermore blocks the negative feedback regulation of E which occurs normally after ovariectomy.

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The Significance of Gonadotropin Ratio in In Vitro Fertilization of Human Oocytes (성선 자극호르몬의 비율이 인간난자의 체외수정에 미치는 영향에 관한 연구)

  • Moon, Shin-Yong
    • Clinical and Experimental Reproductive Medicine
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    • v.15 no.2
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    • pp.135-147
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    • 1988
  • To compare the stimulation effect of the ratio in follicle stimulating hormone and luteinizing hormone in induction of multiple follicular growth, the serum $E_2$ level, the diameter of follicle, number of aspirated follicles and cleavage rate of in vitro fertilized preovulatory oocytes as well as the pregnancy rate were evaluated. Forty one patients with irreparable tubal disease were stimulated by hMG(n=24) or FSH/hMG(n=17) for the purpose of in vitro fertilization and embryo transfer. The following results were obtained. 1. Serum estradiol($E_2$) levels on the day of hCG administration were $921.0{\pm}353.3\;pg/ml$ in hMG group and $1272.9{\pm}1060.6\;pg/ml$ in FSH/hMG group. The serum $E_2$ value of hMG group was significantly lower than that of FSH/hMG group. 2. The diameter of leading follicle by ultrasonogram on the day of hCG administration were $16.2{\pm}2.0\;mm$ in hMG group and $16.2{\pm}2.6\;mm$ in FSH/hMG group. No significant difference of follicle diameter between two groups was demonstrated. 3. The number of follicles with diameter above 10 mm by sonogram on the day of hCG injection were $3.91{\pm}2.32$ in hMG group and $6.52{\pm}3.86$ in FSH/hMG group. There was significant difference of number of follicles between two groups, (p< 0.01). 4. The number of oocytes found per patient at aspiration were $2.59{\pm}1.00$ in hMG group and 3. $76{\pm}2.31$ in FSH/hMG group. There was significant difference of number of aspirated oocytes between two groups. (p< 0.05). 5. The detection rate of preovulatory oocyte at aspiration were 68.4%(39/57) in hMG group (n=22) and 77.6%(38/49) in FSH/hMG group (n=13). 6. The cleavage rate of preovulatory oocyte at 44 hours after insemination were 74.4%(29/39) in hMG group(n=22) and 81.6%(31/38) in FSH/hMG group (n=13). When only hMG was used, one pregnancy was established in 15 patients to whom 29 zygotes were transferred. And a full term normal female baby was delivered by elective cesarean section. In the FSH/hMG group, five pregnancies out of 9 transferred patients were confirmed by serum ${\beta}-hCG$. Two pregnancies were spontaneously aborted before the 6th week of pregnancy. One patient aborted her baby at the 18th week of pregnancy because of incompetent internal os of the cervix. Two patients delivered two full term babies by elective cesarean section. From the above findings, paralell with the increase in the ratio of exogenous follicle stimulating hormone to luteinizing hormone, an increase in oocyte recovery was observed as well as an improvements in pregnancy rate. It was concluded that FSH enrichment early in the follicular phase had a beneficial effect in the controlled ovarian hyperstimulation.

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Effect of Equilibration Time and Cell Stage on the Survival of IVF Bovine Embryos Cryopreserved by Vitrification (한우 체외수정란의 동결보존시 평형시간과 배 발달단계가 생존성에 미치는 영향)

  • 공일근;주영국;이은봉;김용권;박충생
    • Journal of Embryo Transfer
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    • v.9 no.1
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    • pp.7-14
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    • 1994
  • The present experiments on cryopreservation were designed to examine the effects of solution toxicity, equilibration time and cell stages on the post-thaw survival of bovine IVF embryos. The oocytes were matured in vitro(IVM) for 24 hrs. in TCM-199 supplemented with 35 $\mu$g /ml FSH, 10 $\mu$g /ml LH, 1 $\mu$g /ml estradiol-17$\beta$ and granulosa cells at 39$^{\circ}C$ under 5% $CO_2$ in air. They were fertilized in vitro(IVF) by epididymal spermatozoa treated with heparin for 24 hrs., and then the zygotes were co-cultured in vitro(IVC) with bovine oviductal epithelial cells for 7 to 9 days. The bovine IVF embryos were exposed to the EFS solution in one step at room temperature, kept in the EFS solution during different period for toxicity test, vitrified in liquid nitrogen, and thawed rapidly. 1. after the bovine blastocysts were exposed to EFS solution for 2 min. at room temperature and then they were washed in 0.5 M sucrose solution and TCM-199, they were cultured to examined cryoprotectant induced injury during exposure, Most of the embryos(95.0%) developed to reexpanded blastocoels. However, when the exposure time was extended to 5 and 10 min, these development rates dropped dramatically in 5 min. (69.5%) and 10 min. (47.4%), respectively, 2. When the bovine IVF embryos were vitrified in EFS solution after the equilibration for 1 and 2 min. exposure, The embryos to have reexpanded blastocoels following thawing, washing and culture processes were found to he 82.6 and 73.9%, respectively. However, when the exposure time was extended to 3 min, this survival rate dropped to 18.2%. The optimal time for equilibration of bovine IVF blastocysts in EFS solution seemed to he 1~2 min. 3. When the bovine IVF embryos were equilibrated for 1 min. the significantly (P<0. 05) higher post-thaw survival rates were obtained from the embryos of blastocyst stage(81.3%) than morulae stage(5. 1%). The optimal cell stage for viterification with EFS solution proven to he blastocyst stage in bovine IVF embryos. 4. The number of blastomeres of blastocyst stage was examined with nuclear staining with Hoechst 33342 during 7 to 9 days post-insemination. The cell counts of frozen bovine IVF embryos were found significantly(P$\geq$7.5 and those of the fresh embryos 76.6$\geq$7. 1, which were cultured in the sarne period and conditions as frozen embryos.

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Effects of Rearing Condition during the Winter Period on Artificial Maturation and Reproduction of Cultured Female Eel, Anguilla japonica (겨울철 사육조건이 양식산 뱀장어 Anguilla japonica의 인위적인 성성숙 유도 및 번식에 미치는 영향)

  • Kim, Dae-Jung;Kim, Yi-Cheong;Choi, Yong-Ki;Son, Maeng-Hyun;Lee, Jung-Uie;Park, Mi-Seon;Heo, Youn-Seong
    • Development and Reproduction
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    • v.13 no.1
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    • pp.35-41
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    • 2009
  • In the present study, we investigated the effects of rearing condition during the winter period on artificial maturation and reproduction of cultured female eel, Anguilla japonica. The female eel was adapted by combination of environmental conditions (seawater/low temperature, $10^{\circ}C$; seawater/high temperature, $20^{\circ}C$; freshwater/low temperature, $10^{\circ}C$; freshwater/high temperature, $20^{\circ}C$) during 8 weeks of the winter period. Then, the female eel cultivated by different conditions during the winter were transferred to seawater at $20^{\circ}C$ for induction of artificial maturation by salmon pituitary extraction (SPE) injection. The results shown that gonadosomatic index (GSI) and plasma levels of estradiol-$17{\beta}$ (E2) were significantly higher in female eel were reared in seawater than in freshwater, and were the highest at eel adapted by seawater/low temperature. Also, reproduction coefficient were higher in seawater/low temperature than in the other groups. These results will provide valuable information for elevation of the artificial maturation and reproduction coefficient in the cultured female eel.

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