This study was carried out to efficiently use the ultrarapid freezing method in the cryopreservation of mouse ova. For this, the effects of dehydration method, oval vigour and controlling method on post-thawing viability were investigated. Fresh mouse ova were dehydrated in mPBS with 3.5M DMSO and /or 0.25M sucrose, and directly immersed in L for ultrarapidly freezing. The frozen ova were thawed at 37, rehydrated in mPBS with 0.25M sucrose, and then repeatedly washed in HAM's Fl0 before evaluating the morphological normality of frozen-thawed ova. The results obtained showed that there was difference between treatments in a experiment. 1) The post-thawing viability of ova dehydrated in multi-step (48.413.8%) was higher than that of ova in two-step (40.914.0%). 2) The post-thawing viability of fertilized ova (8714.0%) was significantly(p<0.0l) higher than that of unfertilized ova (5.45.4%). 3) The post-thawing viability of ova dehydrated and rehydrated using a cooling machine (95.84.2%) was significantly(p<0.05) higher than that on ice(84.19.9). In conclusion, in order to efficiently cryopreserve ova in vitro with ultrarapidly freezing method, highly viable embryos should be selected, heavy osmotic shock to the dehydrating ova should be avoided, and embryos in high osmotic condition were dehydrated and rehydrated in a constantly low temperature.

본(本) 연구는 micromanipultor를 이용하여 생쥐의 8세포기배와 상실배 그리고 배반포기배를 양분(兩分)후 생존성을 검토하고, 또한 배반포기배를 양분후, 선별(選別)및 배양 과정없이 암컷 생쥐에 이식(移植)하는 경우 새끼쥐 생산의 가능성을 검토하고자 수행된 것이다. 그 경과를 요약해 보면 다음과 같다. 1. 생쥐의 8세포기배(細胞期胚)와 상실배(桑實胚)를 양분(兩分)하여 M2에 배양한결과 각각 64%, 81%가 배반포기배(胚盤胞期胚)까지 발생(發生)하였다. 2. M2 배양액에서 발생시킨 배반포기배를 Ham's F-10에서 배양한 결과 8세포기배에서는 86%, 상실배에서는 90%가 정상적으로 outgrowth 되었다. 3. 배반포기배를 배양 과정없이 바로 양분(兩分)하여 Ham's F-10에서 배양한 결과 97%가 정상적으로 outgrowth 되었으나 암컷생쥐에 이식한 결과 산차는 얻지 못하였다.

본(本) 연구(硏究)는 생쥐에 대한 과배란반응(過排卵反應), 회수(回收)된 수정란(受精卵)의 양분율(兩分率), 양분(兩分)된 분할구(分割球)의 체외배양(體外培養) 및 이식후(移植後) 산자(産仔)로의 발달율(發達率)을 조사하기 위하여 CBA 및 C57BL 계통(系統)의 공시(供試)생쥐에서 얻어진 수정란(受精卵)을 0.5% protease로 투명대 제거 및 미세유리봉으로 양분(兩分)하여 얻어진 분할구(分割球)를 blastocyst로 배양(培養)하여 BALB/C 계통(系統)의 수란(受卵)생쥐에 이식(移植)하여 다음과 같은 결과(結果)를 얻었다. hCG 주사후(注射後) 36~42시간(時間), 48~54시간(時間), 62~66시간(時間), 72~78시간(時間)에 수정란(受精卵)을 회수(回收)한 결과(結果) 각각(各各) 2세포기(細胞期), 4세포기(細胞期), 8세포기(細胞期) 및 상실배기(桑實胚期)의 수정란(受精卵)이 대부분 회수(回收)되었으며 수당(首當) 평균(平均) 17.0개(個)의 난자(卵子)가 회수(回收)되었다. 회수후(回收後) 양분(兩分)한 8세포기(細胞期) 수정란(受精卵)의 양분율(兩分率)은 83.6%로서 상실배(桑實胚)의 65.5%에 비(比)해 유의적으로 높았으나 blastocyst로의 분할구(分割球)의 발달율(發達率)은 상실배(桑實胚)에서 얻어진 분할구(分割球)가 76.5%로서 8세포기(細胞期) 분할구(分割球)의 60.9%에 비(比)해 유의적으로 높았다. 한편 배양(培養)된 분할구(分割球)와 intact embryo에 있어서 세포기(細胞期)에 따라 각각(各各) 수란(受卵)생쥐당(當) 2개(個), 10개(個), 15개(個)씩 이식(移植)하였을 때 공(共)히 15개(個)씩 이식(移植)한 경우 수태율(受胎率)이 가장 높았으나 세포기(細胞期)에 따른 수태율(受胎率)에 있어서 유의적인 차이는 없었다. 배양(培養)된 분할구(分割球)와 intact embryo의 이식(移植)후 새깨생산율(生産率)에 있어서 8세포기(細胞期)에서는 intact embryo를, 상실배(桑實胚)에서도 intact embryo를 이식(移植)하였을때 새끼 생산율(生産率)은 각각(各各) 37.6% 및 43.4%로서 각각(各各) 배양(培養)된 분할구(分割球)를 이식(移植)하였을때 보다 새끼생산율(生産率)이 유의적으로 높았다.

This study was carried out in order to find out better ways for superovuiation and egg collection by checking some factors affecting on donor cows such as iactating and dried, age, season of treatment and sequence of treatment. The results were summarized as follows:1. Number of corpus luteum and collected eggs of eactating and dried doner were 9.8 vs 8.0 and 9.6 vs 7.9,respectively. However, the rate of transferable embryos of lactating doner were higher than that of dried, 82.5% vs 48.1%. 2. The average number of corpus luteum and collected eggs of lactating donors under 7 years of age (6.7 vs lactating 5.3) were slightly lower than those of over 8 years of age (11.1 vs 9.2). But the rate of transferable embryoswas better in under 7 years old donors than over 8 years (81.1% vs 49.3%). were 6.0, 4.8, 1.5, 1.8 and 75%, and those in the summer were 2.9, 3.8, 2.2 and 46.7%, respectively. 3. The average number of corpus luteum was the highest in winter (10.5) and the rate of egg collection was the best in autumn (94.7%). The rate of the transferable embryo was the highest in winter (64.3%). 4. The average number of corpus luteum was the lowest (5.5) in the animals treated six or more superovulating treatments. The rate of egg collection was the best in the third treatment group (90.2%), but it was getting worse after fifth treatment, The rate of transferable embryos was the highest in the second treatment group (94.1%), and it was decreased thereafter.