Developmental characteristics of immature stages of Ostrinia scapulalis (Lepidoptera: Crambidae), which is a main insect pest against legume crops, were investigated at constant temperatures to prepare fundamental data for integrated pest management. Egg, larva and pupa could survive at temperatures from 16oC to 36oC. Developmental periods of those stages became shorter with increasing temperature between 16 and 31oC, 16 and 36oC, and 16 and 34oC, respectively. The lower developmental thresholds and degree-days(DD) were determined as 13.0oC and 56.9DD, 13.8oC and 277.5DD, and 14.2oC and 90.8DD using a linear regression model between temperature and development rate. Other parameters for explaining development of this species were estimated using a few non-linear models for developmental rate, distribution, and survivorship.

Grapholita molesta (Busck) is a major pest of stone fruits. Immature fruits of apricot and plum are well known food source during early summer for G. molesta, but those immature fruits have rarely been evaluated. Thus, we assessed biological and behavioral attributes of G. molesta when provided with immature fruits of apricot and plum in laboratory. The initial response rate (when larva reached to the center from release point in Y-tube olfactometer) of first instar was not different between apricot (70.0%) and plum (60.0%) of which sugar content was more on plum (5.92 brix in apricot and 7.30 brix in plum). However, pupal weight was less in apricot (7.5 mg) than in plum (11.4 mg), and this might be affected by difference in hardness of the fruits (17.2 N on apricot and 13.3 N on plum). The preoviposition period was also longer in apricot (6.3 d) than plum (3.6 d), and fecundity was lower on apricot (64.5) than on plum (135.0). Therefore immature plum fruit would be better food source for G. molesta than apricot during early summer.

Ostrinia zaguliaevi (Lepidoptera: Crambidae) causes serious damage to pods and stems of the red bean, Vigna angularis, during the second half of the reproductive developmental stage. The temperature-dependent development studies of O. zaguliaevi were performed at several constant temperatures ranging from 7℃ to 36℃ in the laboratory, in the purpose of making temperature-dependent development models in the future. Eggs and larvae of O. zaguliaevi could not develop at lower temperatures of 7~13℃. As the temperature increased, the developmental period of the immature stage decreased. The number of larval instar was variable from 5 to 8, depending on temperature. The minimum number of larval instar was observed at only 25℃. Some larvae of colonies maintained at 16~22℃ showed highly longer developmental period. At relatively higher temperatures, 34℃ and 36℃, the larval developmental rates were not slowed down, and the larval survival rates was relatively high, above 60%. The egg mortality was relatively high at 36℃. Using these temperature-dependent development data of O. zaguliaevi, preliminary linear regression equations were estimated to look for a relationship between temperature and developmental rate in egg and larval stages.

This study was conducted to examine the effects of human follicular fluid and gonadotropin (FSH+HCG+rhEGF) on in vitro maturation, fertilization and development of human immature oocytes. Cumulus-oocyte complexes (COCs) were collected following for in vitro fertilization and embryo transfer (IVF-ET) cycles of the patients. At the time of oocytes collection, oocytes were classified into MII, MI and GV in accordance with their appearance (MII: Fully mature oocyte at metaphase II of meiosis; MI: Nearly mature oocytes at metaphase I of meiosis; GV: Immature oocytes at prophase I of meiosis). After controlled ovarian stimulation using gonadotropin(FSH) and human chorionic gonadotropin (HCG) in 70 ICSI cycles, 158 MI to MII matured oocytes were intracytoplasmic sperm injection (ICSI) h after in vitro culture and 553 MII oocytes were ICSI after denudation. The aspirated MI and GV oocytes were cultured in culture medium containing 10% (v/v) serum protein substitute (SPS), 10% (v/v) human follicular fluid (hFF) and 10% (v/v) serum protein substitute (SPS)+1 IU/ml FSH+10 IU/ml HCG+10 ng/ml recombinant human epidermal growth factor (rhEGF). The maturation rate of immature oocytes was similar among the three group. When maturation medium was supplemented with 10% SPS, 10% hFF or gonadotropins, the fertilization rate of in vitro matured oocytes was higher in 10% SPS (80.0%), but there was no statistical significance (78.2%; hFF, 76.9%; gonadotropin, p>0.05). The development rate of human embryos developed to cells were not significant difference in the medium containing SPS, hFF and gonadotropins (65.6%, 65.9% and 66.7%). The results of these study suggest that human follicular fluid and gonadotropins supplemented in the culture medium was not effected on the in vitro maturation, fertilization and development of human immature oocytes.

In the present study, effects of concentration of cryoprotectant solutions on the nuclear maturation of vitrifiedthawed bovine oocytes were examined. Also, the developmental capacity of vitrified-thawed immature oocytes following ICSI was investigated. Oocytes were cultured in TCM-199 medium supplemented with 5% FBS at C in 5% and air. The in vitro maturation rate of vitrified oocytes was 24.5 4.2%. The in vitro maturation rate of vitrified oocytes was lower than that of the control (72.0 3.5%, p<0.05). The in vitro maturation rate of vitrifiedthawed oocytes incubated in TCM-199 medium supplemented with 1.05.0 ug CB were 26.7 3.2%, 35.7 3.2%, 54.0 3.0%, 42.5 3.6%, respectively. The in vitro maturation rate (57.0 3.0%) of the vitrified-thawed oocytes treated with 3.0 g CB for 20 min was the highest of all vitrification groups, although the maturation rate were significantly (p<0.05) lower than those of fresh oocytes. The in vitro maturation rates of the vitrified-thawed (with EDS and EDT) oocytes were 53.8 3.4%, 51.1 3.5%, respectively. This results were lower than the control group (72.0 3.0%). The in vitro developmental rates of the vitrified-thawed oocytes following ICSI were 28.6 4.5%, 25.6 4.3%, respectively. This results were lower than the control group (40.0 4.0%).

In the present study, effects of concentration of cryoprotectant solutions on the nuclear maturation of vitrified-thawed porcine oocytes were examined. Also, the developmental capacity of vitrified-thawed immature porcine oocytes following ICSI was investigated. Oocytes were cultured in NCSU-23 medium supplemented with 5% FBS at in 5% and air. The in vitro maturation rate of vitrified-thawed oocytes () was lower than that of the control (, p<0.05). The in vitro maturation rate of vitrified-thawed oocytes treated with CB + NCSU- 23 medium were , , , , respectively. The in vitro maturation rate () of the vitrified-thawed oocytes treated with CB for 30 min was the highest of all vitrification groups. When the in vitro developmental rates of the vitrified-thawed (with EDS and EDT) oocytes following ICSI were , , respectively. This results were lower than the control group ().

본 연구는 돼지 체외 수정란의 생산에 있어서 체외성숙 시간이 핵성숙, 다정자 침입율 및 배 발생과 배반포의 부화율 배반포의 부화에 미치는 효과를 검토하였다. 돼지 난포란의 핵성숙율이 체외성숙 36, 38, 40, 42 및 44 시간째에 각각 68.0, 78.0, 79.5, 73.8 및 81.8%로서 각 군간에 유사한 경향이었으며, 체외 수정 후 다정자 침입율도 각각 48.7, 36.0, 44.4, 38.9 및 31.8%로서 차이가 없었다. 체외 성숙 시

본 연구는 돼지 미성숙 난포란의 유리화 동결액에 노출시 독성과 삼투압 스트레스가 가장 적은 유리화 동결액을 조사하기 위하여 실시하였으며, 그 결과를 요약하면 다음과 같다. 미성숙 난포란을 EFS(40% ethylene glycol +18% ficoll +0.3 M sucrose) 용액, ES(5.5 M ethylene glycol +1.0 M sucrose) 용액, GE(10% glycerol +20% ethylene glycol) 용액에 각각 노출하고 대조구로 아무 처리하지 않은 난포란을 체외성숙하여 관찰한 체외성숙율은 ES 용액과 대조구 에서 EFS 용액과 GE 용액보다 유의적으로 높았으며(P<0.05), 유리화 동결액의 독성에 의한 난포란의 퇴화율은 대조구, ES 용액, EFS 용액, GE 용액 순으로 유의적으로 낮은 퇴화율을 나타내었다(P<0.05). 미성숙 난포란을 EFS 용액, ES용액, GE용액에 각각 노출하고 대조구로 아무 처리하지 않은 난포란을 체외성숙, 체외수정하여 관찰한 정상 수정율은 대조구가 세 종류의 유리화 동결액보다 유의적으로 높았고(P<0.05), 유리화 동결액 간에는 유의적인 차이가 없었다. 다정자 침입율과 난자당 침입한 평균 정자수는 모든 처리구간에 유의적인 차이가 없었다. 미성숙 난포란을 EFS 용액, ES 용액, GE 용액에 각각 노출하고 대조구로 아무 처리하지 않은 난포란을 체외성숙, 체외수정, 체외 배양하여 관찰한 수정 3 일째의 분할율은 ES 용액과 대조구가 EFS 용액과 GE 용액보다 유의적으로 높았으며(P<0.05), 수정 7일째의 배반포 형성율은 모든 처리구간에 유의적인 차이가 없었다. 배양기간 동안 나타난 퇴화율은 대조구가 세 가지 유리화 동결액에 비해 유의적으로 낮았고(P<0.05), ES 용액은 EFS 용액과 GE 용액보다 유의적으로 낮은 퇴화율을 나타내었다(P<0.05).

To overcome the risk of the ovarian hyperstimulation syndrome (OHSS) in patients have polycystic ovarian syndrome (PCOS) and to prepare emergency fertility preservation in patients undergoing anticancer treatment, several researchers have reported IVM of oocytes retrieved from ovaries exposed by only hCG priming. However, the maturation rate and the developmental potential of embryos from IVM oocytes are significantly lower than those of oocytes matured in vivo. Here, we investigated the optimal time point for immature oocyte collection at post hCG only injection for in vitro maturation, in vitro fertilization and blastocyst formation. Immature GV oocytes were collected from 25 days old B6D2F1 female mouse at 12 hr, 14 hr, 16 hr or 24 hr post hCG injection. Oocytes were collected from antral or late secondary follicle by puncturing with 26 G needle. Collected oocytes were cultured in G2 medium with 10% FBS, FSH, estradiol, and hCG for 16 hr in vitro and subjected in vitro fertilization and further embryonic development. To examine follicular maturation, we estimated the numbers of primordial, primary, secondary follicle and antral follicle on ovaries of each time point post hCG. To confirm the optimal time point post hCG injection for collecting immature oocytes, we recovered the oocytes from each time point. There is no difference in the number of oocytes per mice. Oocytes collected at 14 hr post hCG injection were shown higher maturation rate to MII stage and blastocyst formation compare to other three groups (p<0.01). However, there is no difference in the maturation rate on the other three groups. Also, apoptotic signal with TUNEL assay or anti-PARP staining was not change in ovaries from all experimental groups. Granulosa cell proliferation test with anti Ki-67 or anti AMH was not show any difference. According to these results, there are no significant differences in four different time points at 12 hr, 14 hr, 16 hr or 24 hr of collection of immature oocytes in hCG primed mouse. However, oocytes from 14 hr post hCG injection showed higher percentages of maturation rate, in vitro fertilization rate, blastocyst formation.