The ultrasound-guided oocytes cllection (ovum pick-up ; OPU) has become a substitution for superovlation in cattle. The objective of this study was to examine the effect of OPU frequency on the in vitro production of embryos in Hanwoo cattle. Six cycling Hanwoo cows were distributed into two groups for either once or twice weekly OPU sessions. Oocytes were collected by ultrasound-guided follicle aspiration(SA600) using a 6.5HMz transducer and attached with 18 gauge needle, with vacuum pressure of 40 mmHg. The cumulus-oocyte complexes (COCs) collected from each donor were matured in TCM 199 supplemented with 10% fetal bovine serum at 5% CO2 in air at 38.5 for 22h and in vitro matured oocytes were co-incubated with sperm(separated by Percoll gradient) for 6h. The zygotes were co-cultured on cumulus cell monolayer in 10ul droplets in the same culture medium and conditions used for IVM for 7 days. On Day 7 of culture, development to blastocysts was examined. Although the number of oocytes collected was variable depending on individuals, overall embryo production in the twice per week OPU sessions was better that in the once per week sessions(6~21 vs 2~7 blastocysts produced, respectively). Two cows(E, A) were good oocyte donors and embryo production was superior in cow C ; however, cow F was a poor donor as compared to the others. In conclusion, these results suggest that for embryo production, twice weekly OPU sessions were better than once per week for producing embryos in vitro from Hanwoo cattle

The effect of several potential antioxidants were examined as a means of increasing the in vitro development of in vitro matured and in vitro fertilized oocytes into morulae and blastocysts. Korean native cattle embryos after in vitro fertilization were cultrued for 7 days at 38.5 in CR1aa containing varing concentration of the antioxidants in a gas phases consisting of 5% CO2, 95% humidified air. The results obtained were summarized as follows; The proportion of embryos developed to morulae and blastocysts in CR1aa containing 2.5uM -tocopherol(11.0% and 6.0%) was significantly higher than those of 0, 5.0, and 7.5uM -tocopherol (P<0.05). concentration of 50uM L-ascorbic acid (7.5% blastocysts) did affect the proportion of embryos developing into blastocystes(P>0.05). Addition of 200uM cysteamine was significantly higher than those of 0, 100 and 300uM (P<0.05). When the fertilized oocytes were cultured at 0. 200, 400 and 600uM of selenium for 168 hrs, the morulae rates were 12.2, 5.2, 16.0 and 16.1% respectively, and addition of 200uM selenium was significantly higher than those of 0, 400, 600uM (P<0.05). These results suggested that the addition of -tocopherol, L-ascorbic acid, cysteamine and selenicum can enhanced development to the morulae and blastocysts of in vitro derived fertilized oocytes.

This study was carried out to investigate the effect of co-culture system(bovine oviduct epithelial cells; BOEC) and defined culture system (modified TALP ; mTALP) on the conception of embryos transferred, and pregnancy and twin birth rates after transfer of fresh or frozen-thawed bovine blastocysts produced in vitro were also evaluated. Oocytes from the slaughterhouse ovaries were matured and fertilized using general protocol. The results obtained were as the following. The pregnancy rate after transfer was higher in co-culture group than in mTALP group, but was not signficantly different, and there is no difference between fresh embryo group and frozen-thawed embryo group in conception rate. The conception rate was not different whether 3∼4 blastocysts or 2 blatocysts transferred into a recipient, but the production rate of twin calves was significantly higher (p<0.05) when 3∼4 embryos transferred. The average birth weight of twin calves(24.38kg) was numerically, but not significantly lighter than that of single calves(26.68kg).

This study was carried out to establish an effective system for embryo transfer of techniques by analyzing several factors affecting the gestation length and the weight changes of calves produced from embryo transfer in Korean cattle. The results obtained in study on factors affecting the gestation length and the weight changes of calves produced from embryo transfer were as fallow; 1) The gestation length and the birth weight did not differ between male and female, but the weight changes after birth were remarkablely different between sex(P<0.05). 2) The gestation length between heifers and cows was not different, and body weights at birth and 6 months were remarkabley heavy in cows(P<0.05). Weight changes after 6 months were not different. 3) The gestation length and the birth weight were significantly different between the single and twin calving (P<0.05). Weight of twin at 6 and 12 months were remarkabely light. 4) Calving seasons did not affect the gestation length the and the birth weight. Weaning weight was significantly heavy(P<0.05), but weight changes after weaning were no different among the calving seasons. Conclusivley, this results suggest that cows will be better when considering growth of calves and twin produced from embryo trnsfer in Korean cattle.

모든 낙농경영에 있어서 우분의 관리계획은 중요하다. 본 연구는 옥수수-연맥 작부조합에서 소 액상분뇨의 시용수준을 달리하였을 때 잔여효과로 인한 사료가치, 질소 회수율, 총사초수량 및 토양특성 변화를 구명하고자 1997년 4월부터 1997년 10일까지 축산기술연구소 사료포장에서 수행하였고, 8처리[무비구, 화학비료구(요소) 320 k g N h a − 1 , 계속시용구 320, 640, 960 k g N h a − 1 , 잔여효과구 200, 400, 600 k g N h a − 1 ]를 난괴법 3번복으로 설계배치 하였으며, 그 결과를 요약하면 다음과 같다. 수확 당시 추파 연맥의 평균 초고는 계속시용구가 70.2cm, 잔여효과구가 61.4cm였다. 평균 건물률은 잔여효과구가 계속시용구보다 0.9% 높았으나, 처리간의 유의성은 없었다. 계속시용구가 잔여효과구보다 조단백질 함량은 1.0%, ADF 함량은 1.6%, NDF 함량은 3.1% 높았으며 처리간 유의성도 인정되었다(P<0.05). 사초의 총건물수량은 11,365에서 25 , 668 k g h a − 1 범위로, 960 k g N h a − 1 > 600 k g N h a − 1 > 640 k g N h a − 1 > 400 k g N h a − 1 순이었다(P<0.05). 대조구와 비교하여 비효가는 960 k g N h a − 1 가 158%였고, 600 k g N h a − 1 는 139%였다. 질소회수율은 200 k g N h a − 1 가 50%로 제일 높았고, 그리고 400 k g N h a − 1 , 600 k g N h a − 1 , 320 k g N h a − 1 순으로 높았다. 토양중 치완성양이온함량은 잔여효과구가 계속시용구에 비해 높았다. 이상의 연구결과를 볼 때 옥수수-연맥 작부조합에서 총사초의 건물수량, 비효가, 질소 회수율 면에서 소액상분뇨 600 k g N h a − 1 가 가장 효과적인 것으로 나타났다.

핵 이식에 공여되는 수핵난자의 효과적인 동결보존을 위하여 한우 성숙난자를 1.0 M dimethylsulfoxide(DMSO) 또는 1.0 M glycerol이 함유된 동결보호제를 이용하여 처리하거나, 동결보호제 처리 후 완만동결법을 이용한 동결융핼르 시행하여 상기 실험처리로 야기되는 투명대 경화현상을 관찰하였다. 도축장 유래의 난소에서 미성숙난자를 채취한 후 10% 소 태아혈청을 함유한 TCM-199을 이용하여 22∼24 시간 동안 체외성숙배양을 이해

The development potential of bovine somatic cells was evaluated using nuclear transfer. A single donor cell derived from fetus of HanWoo(Korean Native Cattle) was selected and deposited into perivitelline space of each enucleated oocyte before electrical fusion and activation. Nuclei of donor cells starved for 7 days (37%) tended to support the development of reconstitute embryo the blastocyst stage better than those of donor cells starved 3, 14 and 30 days. The cleavage rate was significantly lower(P<0.05) in reconstitute embryos derived from large size donor cells(51.2%), than those from small medium size donor cells(76.6 and 73.5, respectively). The developmental rate to blastocyst of reconstructed embryos from medium size donor cells was higher than those from small and medium size donor cells. This study demonstrates that an appropriate culture period for induction into quiescent stage and the size of donor cells effect on the efficiency of nuclear transfer using cultured bovine cells.

우리나라 기후조건하에서 액상발효 우분의 시용시기(봄, 가을, 봄/가을 분시)와 시용수준(0, 50, 100, 200 k g N h a − 1 )을 달리 했을 때 토양중의 N O − 3 함량에 대하여 연구한 결과는 다음과 같다. 1. 액상발효 우분의 시용시기는 토양중 N O − 3 함량에 영향을 미치지 않았다. 2. 액상발효 우분의 시용수준 증가는 N O − 3 함량을 증가시켰지만 평균 3.6 m g l − 1 에 불과하였다. 3. 토양의 층별 N O − 3 함량은 0~20cm 깊이에서는 분뇨시용 수준과 비례하여 증가하였고 그 함량도 평균 28.9 m g l − 1 에 달하였지만, 40~60cm층에서는 시용 수준에 관계없이 7.5 ∼ 8.3 m g l − 1 으로 매우 낮았다.

To establish the optimal culture systems for production of transferable embryos in Korean Cattle, pregnancy rates of IVF-derived blastocysts according to different culture media, culture method and culture duration were compared. Development of IVF-derived embryos to blastocysts was most effective in YS medium group co-cultre with cumulus cells. Blastocysts cultured for 6 to 8 d in vitro showed higher hatching rate and good quality. Pregnancy rates after transfer of IVF-derived blastocysts cultured for 7 or 8 d were high. Through our experiments, it is considered that improvement of culture media and culture method is necessary for mass production of blastocysts with excellent of good quality in Korean Cattle.

본 연구는 한우 다배란처리시 노동력을 절감하고 공란우의 스트레스를 방지하여 정상수정란을 안정적으로 생산할 수 있는 1회 주사시 FSH의 용해제의 종류와 농도를 선정하기 위하여 다양한 용매제에 용해시킨 1회 주사와 기존의 다회주사에 의한 난소반응을 비교 검토하였다. 1. 공란우에 다배란 처리후 발정유기는 처리 1과 7에서 100% 유기되었다. 2. 채란수와 정상수정란 수는 처리 1과 처리 7에서 (3.5, 2.9와 3.8, 3.5) 다른 처리구에 비해 유

본 연구는 한우에 있어서 다배란처리에 의한 체내 정상수정란의 생산효율을 극대화하기 위하여 PEG에 용해한 FSH의 1회 피하주사 방법이 현재 사용하고 있는 1일 2회 4일간 근육 주사방법을 대체할 수 있는지를 결정하기 위하여 실시하였다. 연구결과 다회 근육주사 방법과 비교하여 1회 피하주사 방법이 황체수, 총 회수란수 및 이식가능 수정란수에 있어서 현저히 증가 (P〈0.05)하였다. 따라서 한우에 있어서 PEG에 용해시킨 Folltropin-V의 1회

유휴논토양에서 reed canary grass를 재배하였을 때 액상구비의 단기간(3년간) 시용효과를 조사하였으 며, 그 결과를 요약하면 다음과 같다. 1. 모든 예취빈도에서 1993년의 건물수량이 다른 재배년도보다 많았다. 2. 액상구비의 시용수준별 평균 건물수량은 3회 예취구의 360 kg 수준에서 13.10 ton , 4회 예취구의 360~480 kg 수준에서 12.50~12.83 ton 5회 예취구의 450~600 kg 수준에서 12.52~

The objective of this study was to evaluate the embryonic development ability and the appearance of blastocysts of bovine in vitro fertilized oocytes cultured in different culture media, and also to evaluate survival rate after thawing of frozen embryos by using 1.5 or 1.8M ethylene glycol(EG) with sucrose or trehalose. Fertilized oocytes were divided into three groups; i ) monolayer of cumulus /granulosa cell prepared by TGM 199+5% calf serum(TGM199), ii)GRlaa+5% CS, iii)SOF+5% CS, and they were cultured after insemination for 9 days, at 39˚C, under 5% in air, but SOF+5% CS was cultured at 39˚C, under 5% 02, 5% GO2, 99% N2. Blastocysts derived from GRlaa + 5% CS on day 7~8 after insemination were frozen by using 1.5M EG or 1.8M EG with/without 0.2M sucrose or O.1M trehalose. The development rate of blastocysts on day 7 after insemination in SOF+5% CS was significant higher than in TCM199 or CR1aa(P<0.05). The appearance rate of blastocysts on day 7-8 after insemination was higher than in TCM199, when fertilized oocytes were cultured in GRlas or SOF. The survival rate of frozen blastocysts after thawing tended to increase, when blastocysts were frozen by using 1.8M EG with 0.2M sucrose or O.1M trehalose. These results indicated that SOF or CRlaa media with amino acids was superior to TCM199 with monolayer in terms of blastocyst development in culturing of in vitro fertilized bovine nocytes, and sucrose or trehalose was supposed to prevent embryos from the freezing shock.