In vitro development of parthenogenetic embryo was examined after ethanol treatment of follicular oocytes matured in vitro for 42, 48, 54 and 60h in the pig. The follicular oocytes were matured in TCM 199 containing 15% FCS and gonadotrophins in an atmosphere of 39 5% . The cumulus-free oocytes were activated by 10% ethanol treatment in M2+4mg /ml BSA for 10 min. The ethanol-activated oocytes were washed and further cultured in TCM199+20%FCS containing granulosa cell monolayer. Maturation rates at 42, 48, 54 and 60h of IVM were 75.0, 86.5, 81.6 and 87.9%, respectively. Thus the oocytes maturated in vitro for longer periods did not improve nuclear maturation much. Pronuclear formation rates at 18h post-activation in ethanol-activated oocytes were 21.9, 25.0, 47.4 and 32.6%. The cytoplasmic maturation leading to pronuclear formation upon activation increased when the I VM period was extended from 42 to 54h. When the activated oocytes were cultured for 96~120h to analyse early development of the activated oocytes, the rates of embryonic development upto 5~8 cell were 5.3, 5.8, 12.0 and 11.7% among the cultured embryos. The result indicate that earlier development of activated porcine occyte is dependent on the duration of oocyte maturation, and that better development could be obtained from the oocyte matured for 54h.

This study was carried out to investigate the effects of gonadotropins added during maturation of porcine oocytes on the in vitro maturation(IVM), in vitro fertilization(IVF) and developmental potential of embryos. The follicular oocytes were cultured in TCM-199 medium containing different combination of gonadotropins(5g /ml FSR or 1OIU /ml PMSG and 1Og /ml LH or 1OIU /ml hCG), 10% FCS and 10% PFF for 36~48h in a incubator with 5% in Air at 39 and then matured oocytes were again cultured to 120h after IVF for 6~7h with heparin(100g /m')-treated sperm. When the oocytes were matured for 42brs in the medium containing FSH+LH, FSH+hCG, PMSG+LH or PMSG+hCG, the JVF rate of each treatment was 50.0%, 52.9%, 66.7% and 70.0%, respectively. The highest CEI (cumulus cell expansion index) was obtained from PMSG+hCG-added medium and the highest polyspermic penetration resulted from FSH+LH-added medium. The cleavage of IVF oocytes derived from hormone added IVM was significantly(P<0.05) promoted by PMSG+hCG and the cleavage rate after 36-h, 42-h and 48-h maturation aws 53.0%, 56.7% and 45.6%, respectively. The highest developmental potential resulted from the oocytes derived from PMSG+LH -added IVM.

The objective of this study was to develop an effective in vitro production system capable of obtaining more porcine embryos from immature oocytes. These experiments were thus conducted to examine the effect of oocytes type and maturation time on the in vitro maturation(IVM) and fertilization(IVF) of oocytes and the in vitro development (IVD)of IVF embryos. 1. The degree of oocyte maturation based on cumulus expansion index(GEI) did not differ for A- and B-typed oocytes but the index of oocyte type C was lower(P<0.05) than that of other oocyte types. 2. When the oocytes of type A and B were matured for 36, 42 and 48hrs, the GEl was not different between the 36- and 42-h maturation but the GEl after 48hrs was greatly lower(P<0.05) than that of other maturation times. 3. The highest cleavage rate(48.6%) of IVF oocytes was obtained from A typed oocytes and 42-h maturation but the developmental potential based on cleavage index was the highest when B-typed oocytes were matured for 42hrs.

The long term goal of this research is to develop an efficient procedure for large scale production of genetically identical or cloned animals. To improve nuclear transpalntation efficiency in the rabbit, this study evaluated the age of nuclear recipient oocytes on the different steps of nuclear transplantation. The ovulated oocytes in different ages were collected from the superovulated does by flushing oviducts with Dulbecco's phosphate buffered saline(D-PBS) supplemented with 10% fetal calf serum(FCS) from 13 to 15, 17 to 20 and 23 to 26 hours after hCG injection. The denuded oocytes were used as nuclear recipient cytoplasm following enucleation by micromanipulation. The blastomeres separated from the 8-cell embryos were used as nuclear donor. The enucleated oocytes receiving a blastomere in the perivitteline space were fused in the 0.28 M mannitol solution at 1.5 kV/cm, 60 sec for three times. The fused oocytes were co-cultured with the monolayered rabbit oviductal epithelial cells in TGM-199 solution with 10% FCS for 72 hours at 37 in a 5% incubator. The cultured nuclear transplant embryos and in vivo developed embryos collected at 72 hours after hCG injection were stained with Hoechst 33342 dye. Their cell numbers were counted under a fluorescent microscope. The results obtained were summarized as follows ; 1. The aged oocytes(20 hrs. post hCG) showed significantly(P<0.05) higher fusionrates(70 ~ 90%) than the recently ovulated oocytes(30.8%) 2. The aged oocytes which were electrically activated and fused at 20 hours developed to blastocyst at significantly(P<0.05) high rate, while none of the recently ovulated oocytes developed to blastocyst. 3. Even though the aged oocytes at 23~26 hours showed higher fusion rate(85.7%), not only they were inadequate to manipulate but also their developmental potential to blastocyst was highly impaired. 4. The developmental potential in vitro of nuclear transplant embryos was significantly retarded than in vivo deveolped embryos.

This experiment was investigated the effect of presence of granulosa cells from follicles of different size on bovine oocyte maturation, cleavage and development to late stage. The nuclear and cytoplasmic maturation of oocytes in the IVM-IVF system are critical for subsequent embryo development. Granulosa cells when the co-cultured with oocytes may interact with cumulus-oocytes complexes and influence the development competence of the oocytes. Granulosa cells from medium (2~6 mm) and large(>1O mm) size follicles were recovered by aspiration, washed 3 times by centrifugation at 500 x g for 5 min. and used for co-culture at a concentration of 2~3 x 106 cells/mi. The oocytes were matured in vitro (IVM) for 24 hrs. in TCM-199 supplemented with 35 g/ml FSH, 10 g/ml LH, 1 g/ml estradiol-17 and granulosa cells at 39 under 5% 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 (I VC) with bovine oviductal epithelial cells for 7 to 9 days. The assessment of maturation revealed that Grade J oocytes showed significantly(P

소 난자의 시험관내 수정시 이성체인 1, 2 propanediol과 1, 3 propanediol과의 동결보호제의 이용에 대한 독성효과를 조사하였다. 프랑스에 있는 도축장의 난소에서 채취한 미성숙 난자 212개를 시험관내 성숙과 heparin(10g/ml)첨가에 의한 수정 및 배양을 실시하였다. 소 난자의 시험관내 성숙과 수정시 propanediol의 독성효과를 시험한 결과 1,3 propanediol은 80%의 정상 난할분할율과 5.7%의 낮은 다핵분

검정금파리의 변태에 따른 엑디스테로이드를 Radioimmunoassay법으로 측정하고, 난세포성숙에 미치는 엑디스테로이드의 효과를 조사하여 얻을 결과는 다음과 같다. 산락직후 존재하였던 난내 엑디스테로이드는 발생과정 중 감소하다가 부화 직전 다시 증가하였으며, 유충기와 용기의 성장 변태시 엑디스테로이드함량의 변화를 보면 유충-유충과 유충-용으로의 탈피시에 일시적인 증가현상을 나타냈다. 특히 용화 후 48시간에 높은 엑디스테로이드의 농도를 보였는데 이는 큐티클분비와 경화작용과 밀접한 관계가 있는 것으로 생각된다. 성충기에서는 수컷의 경우 엑디스테로이드가 거의 검출 되지 않은 반면, 암컷에서는 단백질원 섭식 후 96시간에 최고의 함량을 나타내어 난성숙도와 일치하는 변화를 보였다. 엑디스테로이드 처리와 난성숙도와의 관계를 보면, 1g 처리군은 대조군에서와 같은 성숙도를 나타내 차이를 보이지 않았으나, 5g처리군에서는 대조군에서 보다 12시간 빠르게 난세포성숙이 완료되어, 엑디스테로이드 처리시 임계농도 이상에서는 난세포조기성숙에 직접적인 영향을 미치는 것으로 나타났다.

The nudear changes of bovine oocytes during 24 hrs. of culture for mejotic maturation were examined. Bovine oocytes were collected from small(<2 mm), medium(2~6 mm) and large(>6mm) follicles and classified into three grades by their morphological characteristics. A total of 242 oocytes collected were obtained:from 184 small, 157 medium and 1 large follicles, respectively and were classified into 95 grade I, 155 grade H and 92 grade III oocytes. All the bovine oocytes collected and graded were washed with a basal medium and incubated in groups of 10 for 24 hrs in 5% and 39. The basal medium used was composed of TCM-199 supplemented with sodium bicarbonate, sodium pyruvate, streptomycin, penicillin G and 10% FCS. The oocytes were cultured in drops of 50,l basal medium supplemented with 35g /ml FSH, 10g /ml LH and 1g /ml estradiol-17. The oocytes were fixed and examined on their chromosomal status by 1% acetorcein staining in the interval of 3 hrs. Most of the grade I oocytes developed to germinal vesicule stage at 0 to 3 hrs., germinal vesicle breakdown at 6 hrs., metaphase I at 9 to 15 hrs., anaphase I and telophase I at 18 hrs., and metaphase II and the first polar body at 24 hrs. after culture for meiotic maturation. However, it was found that compared to grade I oocytes, grade H and W oocytes reached earlier to germinal vesicle breakdown and most of them developed earlier to M II stage at 21 hrs. after culture.

This research was conducted to investigate the interrelationship among methods of injection of PMSG-hCG to the number of ovulated eggs, percentage of matured oocytes and in vitro fertilization using out-bred ICR mice. The results obtained are as follows, 1) The optimurn dose was 5 IU for both PMSG and hCG, while the number of ovulated eggs was 428, percentage of M II was 73% and in vitro fertilization rate was 81 %. 2) The optimum injection interval of PMSG-hCG was 48 hours, while the number of ovulated eggs was 48 8, percentage of M II was 80% and in vitro fertilization rate was 81%. 3) The optimum time for collecting eggs was between 16 and 18 hours after hCG injection, while the numbers of ovulated eggs were 448, 427 and 437 in 14,16 and 18 hours after hCG injection respectively, and percentages of M II were 79 and 81 %, and in vitro fertilization rates were 81 and 80% in 16 and 18 hours after hCG injection, respectively. 4) The repeat of superovulation decreased with the number of ovulated eggs, percentage of M II and in vitro fertilization rate, than in control. But it was recovered by increasing the repeat interval.