This study investigated the effect of variation in the number of somaticcell- cloned embryos and their developmental stage at transfer on pregnancy, as well as the influence of the estrus status of recipient pigs on in vivo development of cloned porcine embryos after embryo transfer. For somatic cell nuclear transfer (SCNT), fibroblast cells were obtained from a male porcine fetus. Recipient oocytes were collected from prepubertal gilts at a local abattoir and then cultured. After SCNT, reconstructed embryos of different numbers and developmental stages were transferred into recipient pigs. The developmental stage of the cloned embryos and the number of transferred embryos per surrogate showed no significant differences in terms of the resulting cloning efficiency. However, the pregnancy rate improved gradually as the number of transferred cloned embryos was increased from 100- 150 or 151-200 to 201-300 per recipient. In pre-, peri-, and post-ovulation stages, pregnancy rates of 28.6%, 41.8%, and 67.6% and 16, 52, and 74 offspring were recorded, respectively. The number of cloned embryos and estrus status of the recipient pig at the time of transfer of the cloned embryo affect the efficiency of pig production; therefore, these variables should be particularly considered in order to increase the efficiency of somatic cell pig cloning.

Poor embryo quality and low blastocyst formation have been major limitations in establishment of cloned embryonic stem cells and production of cloned animals through somatic cell nuclear transfer (SCNT). Aggregation of embryos is a promising method for improving developmental competence of blastocysts. The aim of this study was to improve the blastocyst formation and the quality of parthenogenetic (PA) pig embryos by the aggregation of blastomeres at the 4-cell stage that were cultured in various type of culture dishes with or without phytohemagglutinin (PHA). The PA embryos were produced by the general method of our laboratory. On Day 2 after PA, the zona pellucida of 4 cell-stage embryos were removed by treatment with 0.5% (wt/vol) pronase solution. The 3x zona-free blastomere (ZFB) were randomly distributed in each of the following treatments for aggregation. ZFB were cultured for 5 days at 39℃ in an atmosphere 5% CO2, 5% O2, and 90% N2. In Experiment 1, effect of culture dishes on the aggregation efficiency and developmental competence of PA embryos were investigated. ZFB were cultured on non-coated (control) culture dish or dishes coated with 1% (wt/vol) agarose substrate (AS) or Well of the Well in dishes coated with 1% (wt/vol) agarose substrate (WAS). The ZFB cultured in WAS showed significantly higher (P<0.05) aggregation (81.2%) than AS and control (21.6-45.5%). The mean cell number in blastocysts derived from AS and WAS (81.4-89.3 cells/blastocyst) was significantly higher (P<0.05) than that of control (63.8 cells/blastocyst). In Experiment 2, effects of 150 ug/ml PHA treatment on the aggregation efficiency and developmental competence of embryos were investigated. The ZFB cultured in AS with PHA showed a higher (P<0.05) aggregation rate (90.0%) than that in AS without PHA, control with PHA, and control (39.2%, 57.9% and 17.5%, respectively). In conclusion, aggregation of porcine ZFB treated with PHA and agarose substrate could be a useful technique for producing improving blastocyst development with increased mean cell number of blastocysts in pigs.

The Somatic cell nuclear transfer (SCNT) method can be applied to various fields such as species conservation, regenerative medicine, farming industries and drug production. However, the efficiency using SCNT is very low for many reasons. One of the troubles of SCNT is that it is highly dependent on the researcher’s competence. For that reason, four somatic cell nuclear injection methods were compared to evaluate the effect of hole-sealing process and existence of cytochalasin B (CB) on efficiency of murine SCNT protocol. As a results, the microinjection with the hole-sealing process, the oocyte plasma membrane is inhaled with injection pipette, in HCZB with CB was presented to be the most efficient for the reconstructed in SCNT process. In addition, we demonstrated that the oocytes manipulated in Hepes-CZB medium (HCZB) with CB does not affect the developmental rate and the morphology of the blastocyst during the pre-implantation stage. For this reason, we suggest the microinjection involving hole-sealing in HCZB with CB could improve SCNT process efficiency.

Bovine somatic cell nuclear transfer (bSCNT) embryos can develop to the blastocyst stage at a rate similar to that of embryos produced by in vitro fertilization (IVF). However, the efficiency of somatic cell cloning has remained low, and applications have been limited, irrespective of the nuclear donor species or cell types. One possible explanation is that the reprogramming factors of each oocyte is insufficient or not properly adapted for the receipt of a somatic cell nucleus, because it is naturally prepared only for the receipt of a gamete. Here, we would like to introduce the aggregation method (agSCNT), a new experimental system that enables and increase oocyte volume and examined its subsequent development. Judgement by the blastocyst formation rate or total cell number was significantly higher in the agSCNT group than that in the SCNT group, and was very similar to that in the control IVF group. Moreover, the cleavage formation rate in the agSCNT group (61.5 ± 1.3) was higher than that in the SCNT group (39.7 ± 2.1), while still less than that in the IVF group (75.4 ± 1.3). We also analyzed the epigenetic modifications in bovine IVF, agSCNT, and untreated SCNT embryos. In conclusion, the present study demonstrated that agSCNT improves the in vitro developmental competence and quality of cloned embryos, as evidenced by increased total cell numbers (TC).

The clustered regularly interspaced short plalindromic repeats(CRISPR)/CRISPR associated protein (Cas9) system can be applied to produce transgenic pigs. We applied CRISPR/Cas9 system to generate hG-CSF targeted pig parthenogenetic embryos. Using sigle guided RNA targeted to pig hG-CSF genes was injected into cytoplasm of in vitro matured oocyte before electrical activation. The CRISPR/Cas9 vector were diluted in Tris-EDTA buffer (TE buffer) and injected with different concentration of 0 (sham injection), 2.5 and 25 ng/ul. In results, regardless of the concentrations of vector, the cleavage and blastocyst rate were not significantly different among three groups. Since plasmid DNA was used for microinjection, we investigated whether DNA vectors were integrated into the genome. Genomic PCR of the coding sequence of Cas9 variants and hG-CSF was performed to detect genomic integrants. Each blastocysts were collected into a microtube, and then PCR was performed. Overall 32 embryos are not expressed targeted gene.

The cryopreservation of Hanwoo embryos has become an integral part of assisted reproduction in animal. The objective of this study was to assess the effect of The objectives of this study were: (1) to evaluate the influence of bovine embryo developmental stage on in vitro embryo development after freezing, (2) to study the efficiency compared with conventional freezed embryos at different embryo source. For conventional slow-freezing, day 7 or 8 expanded blastocysts were collected. The standard freezing medium was 1.8 M ethylene glycol (EG). Embryos were equilibrated in 1.8 Methylene glycol(EG) with 0.1 M sucrose in Dulbecco's phosphate-buffered saline (D-PBS) supplemented with 0.5% bovine serum albumin. Embryos were then loaded individually into 0.25 ml-straw and placed directly into cooling chamber of programmable freezer precooled to , after 2 min, the straw was seeded, maintained at for 8 min, and then cooled to at /min, plunged and stored in liquid nitrogen for at least 3 days. For thawing, the straw containing embryos were warmed in air for 10 see and exposed to water for 20 sec. Straws were then removed from water. Rates of blastocyst survive and hatched were evaluated at 12 to 48h post-warming. The re-expansion and hatched rates of morula embryos were significantly lower than those obtained for blastocysts and expansion blastocysts (31.6%, 10.5% vs, 68.9%, 22.2% vs, 73.7%, 53.6%, respectively). No differences in re-expansion rates were found between in vivo and in vitro blastocysts. whereas hatched rates was significantly higher (51.2%) in vivo compared with in vitro embryos (18.6%). in conclusion, demonstrate that conventional freezing can be used successfully in cryopreservation of in vitro and in vivo bovine embryos, and that it might be considered for use in commercial programs and embryo preservation.

목적 : 본 연구의 목적은 발달장애 아동의 조기 중재를 위해 개발한 인터넷 재활상담의 효율성을 연구하고자 하였다. 연구방법 : 연구대상은 2000년부터 2004년까지 홈페이지(www.ddchild.com) 질문게시판을 이용하여 인터넷 재활상담을 요청한 997명의 상담내용을 분석하였다. 결과 : 4년 동안 인터넷 상담을 이용한 받은 997명 중 88%는 장애아의 부모였고, 상담을 의뢰한 아동은 1-6세의 아동이 전체의 84%였고, 1세 이하의 아동이 12%였다. 상담을 의뢰한 아동의 74%는 이미 발달지연, 자폐, 정신지체, 언어장애 등의 진단명을 받은 상태였고, 29%의 아동은 진단명을 받지 않은 고위험군에 속하는 아동군이었다. 이용자가 원하는 치료와 교육을 원하는 서비스 영역은 언어치료(25%), 행동수정(22%), 운동치료(18%), 사회성 훈련(15%), 학교진학(8%) 순으로 나타났다. 그러나 전문가에 의해서 상담서비스가 이루어진 영역은 행동수정(35%), 감각통합(34%), 언어치료/교육(12%), 물리치료(12%), 학교진학 상담(9%) 순이었다. 결론 : 인터넷을 통한 장애아동 조기발견, 조기치료와 교육상담은 조기교육 현장을 대체하는 저비용/고효율의 사회안전망 역할수행이 가능함을 이 연구에서 보여주고 있다. 이용자의 대부분이 부모이고, 장애아동 뿐만 아니라 비장애 아동 부모의 참여도 높아 고위험군 아동의 조기발견/조기개입을 통해 장애 예방에도 인터넷 재활상담의 역할이 크게 기대된다. 특히 우리나라는 인터넷망이 잘 구축되어 있어 부모들이 인터넷에 쉽게 접근할 수 있고, 신분노출이나 금전적 부담 없이 원하는 상담과 정보를 지원받을 수 있는 장점이 있어, 인터넷 재활상담은 장애아동 조기교육에 대한 사회안전망이 미흡한 국내에서는 장애 영유아 조기교육을 위한 공교육 대안으로서 적극적으로 활용해볼 가치가 있겠다.

The study evaluated the effect of donor cell treatments for G0/Gl synchronization and the donor ceil type on development and incidence of apoptosis in cloned cattle embryos. Primary cultures were established from a female fetus on day 50 of gestation and