• 대한생식의학회:학술대회논문집
• /
• 2001.11a
• /
• pp.110-110
• /
• 2001

• 대한생식의학회:학술대회논문집
• /
• 2002.05a
• /
• pp.70-71
• /
• 2002

• Korean Journal of Animal Reproduction
• /
• v.24 no.1
• /
• pp.83-88
• /
• 2000

This study was conducted to determine the effect of repeated ultrasound-guided transvaginal retrieval of oocytes recovery, estrous cycle and ovarian adhesion in Korean native, Hanwoo heifers. Heifers were at unknown stages of the estrous cycle at the start of experiments in which all follicles $\geq$6mm in diameter were ablated. The results obtained in this study were as follows; Follicle developing number and oocytes collected number were no effected to repeated OPU to nine session, 4 e.a range oocytes collected to repeated OPU session. Oocytes were observated follicles were 8.7$\pm$4.2 e.a, collected oocytes were 4.1$\pm$3.4 e.a to two times collected per week and observated follicles was 10.2$\pm$6.1 e.a, collected oocytes were 4.3$\pm$2.9 e.a to one times collected per week, but no difference significantly(P＜0.05). Ovaries adhesive percentage to repeated OPU was eight ovaries adhisived(20%) of forty ovaries, three ovaries(7.5%) to 1~3 times oocytes collected, four ovaries(l0%) to 4~6 times, one ovaries(2.5%) to 7~9 times oocytes collected session. To repeated OPU effection, ovaries adhisive heifers were long estrous cycle(＞25 day) to 7 heads(87.5%) of 8 head, non-adhesive ovaries heifers were 5 heads(41.7%) were long estrous cycle to repeated OPU 12 heads. Although, now unknown about the dynamics of follicles wave and about functional changes to repeated OPU ovaries, more question about ovaries adhesive cause remain.

• Reproductive and Developmental Biology
• /
• v.28 no.3
• /
• pp.181-185
• /
• 2004

This study was conducted to examine whether activation treatments, source of oocytes and culture conditions affect in vitro developmental ability of caprine oocytes. Mature Korean native goats were pretreated with intravaginal CIDR for 10 days. The goats were then treated with a single intramuscular injection of 1,000 IU PMSG on Day 8 or twice daily injection of a total of 70 mg FSH for 3 days from Day 8 of CIDR insertion for superovulation. All the goats were injected with 10 mg PGF/sub 2a/ on Day 8 and 400 IU hCG on Day 10 of CIDR. Oocytes were surgically collected by oviduct flushing(in vivo maturation) or direct follicle aspiration(in vitro maturation) through mid-ventral incision at 35 h after hCG injection. Fifteen to twenty oocytes were placed in TCM-199 medium containing 25 mM Hepes and hormones under mineral oil at 39℃ in a humudified atmosphere of 5% CO₂ in air for 22 to 24 h. After maturation, the oocytes were activated by electric stimulation or ionomycin + 6-DMAP. The activated oocytes were then cultured in M16, TCM-199 and mSOF media supplemented with proteins at 39℃ for 6 to 7 days. Activation treatments did not affect cleavage of the oocytes. The cleavage rates were 64.1% (41/64) in oocytes activated by electric stimulation and 76.5% (218/285) in oocytes activated by ionomycin + 6-DMAP. The proportion of development to blastocyst was 15.6% (34/218) in oocytes activated by ionomycin + 6-DMAP, but activation by electric stimulation did not support embryos developed beyond morula stage. There were no differences in the cleavage rates of activated oocytes experiencing in vivo (86.8%, 66/76) and in vitro maturation (69.0%, 127/184). However, the development rate to blastocyst stage was significantly (P<0.05) higher for oocytes matured in vivo (50.0%, 33/66) compared to in vitro (0.8%, 1/127). Culture conditions did not affect the cleavage of -activated oocytes. The cleavage rates were 51.6% (49/95) in M16, 64.3% (18/28) in TCM-199 and 81.0% (145/179) in mSOF, respectively. By contrast, the development rate of activated oocytes to stage was greater (P<0.05) for oocytes cultured in mSOF medium (23.4%, 34/145) than in M16 or TCM-199 (0.0%). Our results suggest that source of oocytes and culture conditions are major factors affecting in vitro development of caprine parthenogenetic oocytes.

• Journal of Life Science
• /
• v.8 no.5
• /
• pp.576-581
• /
• 1998

The present study was carried out to investigate the effect of gonadotropin administration on the timing of ovula-tion, fertlizable life of eggs and cleavage of embryos in rabbit. Mature angora rabbits were primed for superovulation with PMSG 100IU. Eighty hours later, the rabbit were induced to ovulate with HCG 100IU. Ovulation had started at 10hours after HCG injection and finished at about 16hours. Fertilizable life of eggs were lasted for 8hours after ovulation. The most frequent developmental stage observed from the embryos recovered at 24, 48, 72, 96, and 120 hours after HCG injection was 2-ceIL, 16-cell, morula, blastocyst and blastocyst, respectively.

• Journal of Embryo Transfer
• /
• v.29 no.3
• /
• pp.265-271
• /
• 2014

Implementation of smart embryo technologies in cattle e.g. ovum pick-up followed by in vitro embryo production (OPU-IVP). Seasonal variation is important factor for follicular growth, oocytes quality, quantity and developmental competence. Therefore the aim of present study was carried out to investigated whether the seasons (hot and cool) effect on follicular development, oocyte recovery and subsequent embryo development. Follicular oocytes were aspirated from Korean native cows (Hanwoo) by the ovum pick-up (OPU) method, which was performed 24 times during two different seasons, the hot (July to September) and cool (October to December), from OPU donors. The recovered oocytes were classified according to morphological categories and used for in vitro embryo production (IVEP). The mean number of total follicles was significantly higher (p<0.05) during the hot season ($18.32{\pm}2.26$) compared to cool season ($15.41{\pm}3.34$). Furthermore, seasons did not significantly effect on the number of oocytes recovered (hot season: 41.16% vs. cool season: 46.14%). However, the average number of Grade A oocytes was significantly greater during hot ($1.75{\pm}1.86$) season compared to the cool season ($1.00{\pm}1.46$), but there was no significant difference of other grades oocytes. The cleavage rate (hot: 66.67% vs. cool: 63.3%) and embryo development (hot: 58.95% vs. cool: 56.97%) did not differ significantly between the seasons. In conclusion, the results of present study suggest that the season (hot and cool) does not have effects on the oocyte recovery and embryo developmental competence of in vitro cultured embryos.

• Korean Journal of Animal Reproduction
• /
• v.26 no.2
• /
• pp.105-110
• /
• 2002

The objective of this study was to determine the developmental competence of in vitro matured oocytes after intracytoplasmic sperm injection(ICSI) with epididymal spermatozoa. The ovaries were obtained from slaughtered small species dogs. Oocytes matured in vitro for 24 hrs were fertilized by ICSI with epididymal spermatozoa. After ICSI, one group of oocytes was activated with 2.0 mM dimethylaminopurine or 7% ethanol for 5 min. and second group was not activated. The follicular oocytes were cultured in synthetic oviductal fluid(SOF) and TCM-199 medium containing hormones and 10% FCS for 24~48 hrs in a incubator with 5% $CO_2$ in air at 38.5$^{\circ}C$. 1. Results of IVM showed that the percentage of oocytes reaching MII after 24 h and 48 hrs of incubation were significantly higher(p<0.05) after culture with 48 hrs(9/30, 30.0%) than that after culture with 24hrs(a/30, 26.7%). 2. Results of IVM showed that the percentage of oocytes reaching MII after 48 hrs of incubation were significantly higher(p<0.05) after culture with SOF media(10/30, 30.3%) than TCM-199 media (7/30, 23.3%). 3. The rate of cleavaged embryos to blastocyst obtained by ICSI treated activation oocytes was significantly higher(p<0.05) than that of nonactivation oocytes(5/16, 25.0% vs 1/13, 5.0%). 4. The rates of development of cleavaged embryos to blastocyst obtained by ICSI treated sperm of fresh, epididymal and frozen-thawed epididymal were 8/18(44.43%), 5/16(31.3%), 2/14(14.3%), respectively. and these values of frozen-thawed epididymal sperm injection were lower than fresh sperm injection.

• Reproductive and Developmental Biology
• /
• v.30 no.1
• /
• pp.7-11
• /
• 2006

This study was conducted to examine the effects of hormone and sodium pyruvate on in vitro maturation of canine oocytes. Canine oocytes were collected from the ovaries of dogs and cultured in NCSU-37 medium with hormones and sodium pyruvate for 72 hr. Oocytes matured to the metaphase II (MII) stage were observed only from estradiol $17{\beta}\;(E_2)$, and the presence of gonadotropin did not improve the nuclear maturation. No oocytes were developed to the MII stage when $E_2$ was added to medium during the first 6 and 24 hrs of culture period. The presence of $E_2$ during the whole culture period enhanced the nuclear maturation to the MII stage (6.0%, P<0.05). High concentration of sodium pyruvate (2.5 mM) slightly enhanced the nuclear maturation to the metapahse I (HMI) stage, but not the MII stage. the result of the present study shows that the presence of $ E_2$ during the whole culture period of 72 hr enhances the maturation of canine oocytes to the M stage, but sodium pyruvate does not affect the nuclear maturation of the canine oocytes.

• Journal of Embryo Transfer
• /
• v.25 no.1
• /
• pp.15-20
• /
• 2010

This study was performed to identify the optimal timing for oocyte donor replacement during OPU procedure. OPU was carried out to collect oocytes from every donor at an interval of $3{\sim}4$ days (2 times a week). The collected oocytes were matured in vitro in TCM-199 supplemented with 10% FBS, 10 mg/ml of FSH and 1 mg/ml of estradiol for 24 h. After 24 h of exposure to sperm, the presumptive zygotes were cultured in CR1aa medium supplemented with 4 mg/ml of BSA for 3 days before being changed to CR1aa medium with 10% of FBS for another $3{\sim}4$ days. The mean numbers of retrieved oocytes were remained constantly up to 3 months ($6.0{\pm}0.5$, $6.2{\pm}0.7$, $5.2{\pm}0.6$), but significantly decreased at over 4 to 6 months ($3.7{\pm}0.5$, $2.8{\pm}0.4$, $1.2{\pm}0.2$) (p<0.05). The blastocyst development potential was also very similar rate from 1 to 3 months (37.2%, 40.4% and 44.6%), but significantly decreased from 4 to 6 months (24.8%, 29.3% and 28.6%, respectively) (p<0.05). The production of OPU derived embryos in periods of 1 to 3 months ($2.2{\pm}0.3$, $2.5{\pm}0.3$ and $2.3{\pm}0.4$) were significantly higher than those in 4 to 6 months ($0.9{\pm}0.2$, $0.8{\pm}0.2$ and $0.3{\pm}0.2$, respectively) (p<0.05). In conclusion, the efficient periods for the production of OPU derived embryos was until 4 months, twice per week to produce over 64 transferable embryos and then replace new donor after 3 months use. The best replacement time is 3 months and could be maximized production of OPU derived embryos.

• Korean Journal of Animal Reproduction
• /
• v.25 no.2
• /
• pp.125-130
• /
• 2001

This study was performed to report a direct dose dependent stimulatory effect of the Flavonoid(F) on basal testosterone secretion and a dose dependent effect on LH induced testosterone production by Leydig cell of matured rats in vitro culture. F was obtained kom the Rhus vernicifua through aceton extraction and silica gel adsorption column chromatography. Leydig cells (1$\times$10$^{6}$ cells/well) from 12 weeks old rats were incubated with or without F(0, 20, 40, 80, 160 ng) or insulin-like growth factor-I(IGF-I) in the presence or absence of LH(10, 100ng). 1. The maximal stimulatory concentrations of testosterone in culture media were showed at 24hr of culture. but these testosterone level were decreased at 36 hr of culture. 2. Flavonoid(80ng) were significantly(P ＜ 0.05) increased testosterone production compared with control groups for 12 hr culture. 3. Testosterone secretion by Leydig cells stimulated with LH(10, 100ng) for 6 hr and 12hr culture compared with 3 hr culture. 4. LH 10 ng augmented testosterone were increased by addition of F 40 ng for 12 hr culture. 5. F(0 and 40 ng) also enhanced LH 10 ng stimulated testosterone for 3 hr Leydig cells culture. 6. Addition of IGF-I 100 ng to the culture medium for 6 hr were increased the concentration of testosterone by Leydig cells stimulated with 100 ng LH. These results indicate that Flavonoid has a direct stimulatory effect on basal testosterone secretion in rat Leydig cells, and also modulates LH mediated testosterone. Therefore, Flavonoid may act as a modulator on gonadal development or gonadal steroidogenesis in direct or indirect.