• 한국수정란이식학회지
• /
• 제12권3호
• /
• pp.325-333
• /
• 1997

수정란이식의 주변기술인 초기배의 미세조작및 성 판정은 가축의 경우, 경제 형질의 유전적 개량에 크게 기여하였다. 본 연구는 미세조작 biopsy와 PCR에 의한 체외생산 소 초기배의 급속. 정확한 성 판정 기법을 확립하기 위해 실시하였다. 체외성숙 및 체외수정에 의해 생산된 소수정란은 소 난관상피세포와 공배양을 통해 8-세포부터 배반포시시까지 체외발생시킨 후 미세조작 biopsy에 이용되었다. 미세조작 biopsy 과정중에 약간의 형태적인 손상이 관찰되었지만 대부분의 demi-embryo는 정상적인 배반포와 나화배반포로 발생하였다. 8~16 세포, 상실배, 초기배반, 포 시기에서 미세조작 biopsy 후 확장 또는 나환배반포기시기까지의 발달율은 각각 62.8(27/43), 83.3(30/36) 및 80.9%(55/68)로 정상적인 초기배와 큰 차이가 없는 것으로 나타났다. 총 136개의 소 초기배로 부터 2~10개의 할구세포를 미세조작 biopsy에 의해 분리하여 소 특이와 Y-특이염기서열을 가진 두 쌍의 염기서열을 이용하여 PCR을 수해하였다. 이들중 112(82.4%)개를 성공적으로 성 판정하였으며, 암/수 비율은 각각 34.8(39/112)/65.2%(73/112)로 나타났다. 본 실험에서 얻은 결과는 확립된 소 초기배의 미세조작기술과 성 판정 방법을 통해 계획적인 암.수 송아지의 선별 생산뿐만 아니라 소 수정란 이식을 통한 유전적 개량을 촉진시키는데 효과적으로 이용될 수 있는 기술이 확립된 것을 보여주었다.

• 한국가축번식학회지
• /
• 제13권2호
• /
• pp.113-120
• /
• 1989

In order to determine the sex of preimplantation embryos prior to transfer in cattle, a series of experiments were carried out using 45 Holstein donor cows to examine the ovarian response on the gonadotropin and PGF2${\alpha}$, and the morphology of fresh embryos or frozen/thawed embryos after deep freezing at -196$^{\circ}C$. The sexing of embryos treated with the medium containing H-Y antiserum(10%, v/v) and FITC anti-mouse IgG(10%, v/v) were analysed by chromosomal analysis, and the sex of the embryos which survived were ascertain after delivering the pups. The results obtained were summarized as follows ; 1. The average number of developed follicle and corpus luteum per cow were 13.5 and 8.1, and the ovalation rate was 60.1%. 2. Of 220-ova recovered, 75(34.1%) were morula and 91(41.4%) were blastocyst, and the morphological normal and abnormal rate of ova recovered were 75.5% and 24.5%, respectively. 3. Of 39 frozen/thawed embryos, the scores of normal morula and blastocyst, after thawing were 79.2%(19/24) and 73.3%(11/15). The average rate of frozen/thawed embryos which appeared morphologically normal post thawing was 76.9%(30/39). 4. The sex ratio was measured using the embryos treated with immunofluorescence assay to examine the relationship between embryo developmental stage, sex ratio of morula stage embryo was 42.2%(19/45) fluorescing and 57.8%(26/45) non-fluorescing, on the other hand, the ratio switched to 46.8%(29/62) fluorescing and 53.2%(33/62) non-fluorescing embryo in blastocyst stage. The sex ratio was also measured between fresh and frozen/thawed embryos, fresh and frozen/thawed treated embryos were indicated 45.8%(38/83) fluorescing, 54.2%(45/83) non-fluorescing and 41.7%(10/24) fluorescing, 58.3%(14/24) non-fluorescing. This trend indicated the approximal sex ratio was 1 : 1. 5. The result of karyotype test showed the successful rate of sexing embryo is fluorescing and non-fluorescing was 21.2%(7/33) and 29.6%(8/27). The female to male ratio within 33 fluorescing was 28.6 : 71.4, and the ratio of 27 non-fluorescing embryos was 87.7 : 12.5. 6. Of the embryo transferred after assignment of H-Y phenotype, five of the fluorescing embryos survived to term, all was males. Whereas six non-fluorescing embryos also survived to term and the sexes of the calves were 1 male 5 female.

• 한국동물번식학회:학술대회논문집
• /
• 한국동물번식학회 2001년도 발생공학 국제심포지움 및 학술대회 발표자료집
• /
• pp.5-5
• /
• 2001

This lecture will begin by tracing some of the history behind techniques that we nowadays take for granted in the practice of embryo transfer, and in the application of the technique to various animal biotechnologies. It will be argued that an appreciation of such history can teach us a great deal about how we need to study and teach the subject, and about the best ways to conduct and finance the research that is essential to further progress. Examples in support of this argument will be taken from the changes that have occurred in the way embryos, particularly bovine embryos, have been collected, maintained in vitro, subjected to a variety of manipulations (sexing, division to produce identical animals, combination into chimeras, transfection with foreign genes), frozen and thawed, and transferred over the past 50 years. (omitted)

• 한국가축번식학회지
• /
• 제17권4호
• /
• pp.305-310
• /
• 1994

These expriments were carried out to investigate existence of H-Y antibody in the rat serum immunized against H-Y antigen from rat spleen cells and effect of H-Y antiserum on development of mouse male embryos. The results obtained were summerized as follows : 1. When mouse embryos were cultured for 48∼72 hrs in the Ham's F10 containing 16% of FBS(fetal bovine serum) or RNS(rat normal serum), percentages of embryos developed from 2, 4, 8 and 16-cell embryo to morulae were 20, 27, 94 and 100%, respectively, in FBS and 8, 7, 94 and 100%, respectively, in RNS. Eight to 16-cell embryos showed no difference in development rate between FBS adn RNS. 2. When 8∼16-cell mouse embryos were cultured for 24∼48 hrs in the Ham's F10 containing FBS, RNS＋GPC(guinea pig complement) and RAS(rat antiserum)＋GPC, proportions of embryos developed to the expanded blastocyst stage were 100, 82.4 and 52.1∼53.6%(ave.52.9), respectively, so that it was suggested that rat antiserum suppressed development of male embryos. 3. When 8∼16-cell mouse embryos were cultured for 24∼48 hrs in the Ham's F10 containing FBS, RNS, RNS＋GPC and RAS＋GPC, proportions of embryos developed to the expanded blastocyst stage were 94.5, 90.9, 82.3 and 47%, respectively, and the embryos developed in the medium containing RAS＋GPC seemed to be female. These results indicated that the antisera prepared through immunized against H-Y antigen from rat spleen cell, possessed H-Y antibody which supressed development of male embryos.

• Animal Bioscience
• /
• 제36권6호
• /
• pp.973-979
• /
• 2023

Objective: The clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated protein 9 (Cas9) system, which is the most efficient and reliable tool for precisely targeted modification of the genome of living cells, has generated considerable excitement for industrial applications as well as scientific research. In this study, we developed a gene-editing and detection system for chick embryo sexing during the embryonic stage. Methods: By combining the CRISPR/Cas9 technical platform and germ cell-mediated germline transmission, we not only generated Z chromosome-targeted knockin chickens but also developed a detection system for fluorescence-positive male chicks in the embryonic stage. Results: We targeted a green fluorescent protein (GFP) transgene into a specific locus on the Z chromosome of chicken primordial germ cells (PGCs), resulting in the production of Z^GFP-knockin chickens. By mating Z^GFP-knockin females (Z^GFP/W) with wild males (Z/Z) and using a GFP detection system, we could identify chick sex, as the GFP transgene was expressed on the Z chromosome only in male offspring (Z^GFP/Z) even before hatching. Conclusion: Our results demonstrate that the CRISPR/Cas9 technical platform with chicken PGCs facilitates the production of specific genome-edited chickens for basic research as well as practical applications.

• 한국수정란이식학회지
• /
• 제3권1호
• /
• pp.48-52
• /
• 1988

우수정란의 이식전 성판별이 관한 연구를 수행하기 위하여 GTH와 PGF$_2$$\alpha$투여에 대한 난소반응과 회수난자의 발유단계별 동결융해후 생존성을 조사하였으며, 이식전 수정라느이 성판별을 위하여 H-Y항체 처리후 정상발육 난자의 염색체를 분석하여 다음과 같은 결과를 얻었다. 웅성 비장세포(male, spleen cells)를 면역원으로 mouse와 rat에 투여, 항혈청의 항체를 확인한 결과 mouse에서는 C57 BL계통과 rat에서는 DonRyu 계통이 항체생산능력이 우수하였다. 공란우 87두에 hormone(2500IU PMSG, 25mg PGF$_2$alpha)처리하여 평균 57.8%의 채란유과 두당 4.9개의 난자가 회수되었으며, 전체회수란자(427개)중 moula(162개)와 blastocyst(190개)의 정상발육란자는 82.4%였다. 동결융해후 회수된 난자 (312개)중, 형태적으로 정상인 난자(241개)의 비율은 77.2% 발육단계별 성적은 blastocyst(83.4%)가 morula(71.0%)보다 우수하였다. 항체와 보체(Guinea pig serum)로 처리된 82개의 morula중 15개(18.3%)가 blastocyst로 발육되어 이중 5개(33.3%)가 성이 판별되었으며, 모두 xx형 성염색체를 갖는 자성수정란으로 판명되었다.

• 한국수정란이식학회지
• /
• 제30권2호
• /
• pp.73-82
• /
• 2015

This study was designed to evaluate the possibility of increase through dairy female offspring's ratio by transfer of pre-selected transferrable blastocyst that was produced by pre-selected X-bearing semen with OPU derived oocytes. Elite dairy female cow is demanded strongly compared with male, the so called, farmer wants to produce only an elite female dairy offspring as a candidate female dairy cow for producing milk. In our study, we selected 2 elite dairy bull semen from National Agricultural Cooperative Federation to pre-select X-bearing semen and 5 elite dairy female cows as donor for collecting of OPU derived oocytes. OPU derived embryo production system was carried out an aspiration of immature oocytes from 5 donor cows 2 times per week, total 200 times for 2 to 7 months by an ultrasonographic guided follicular aspiration system and then produced in vitro-produced blastocysts by in vitro maturation, fertilization and culture. Dairy donor semen selected H-319, 320 bull in National Agricultural Cooperative federation was sorted X-bearing semen by flow-cytometer and frozen for using IVF with OPU derived oocytes. Donor cows were selected 5 elite dairy cows from Gyeongju Dairy Cow Community and then disease tests such as 4 kinds of disease before selecting was checked. Oocyte proportion of grade 1 to 3 from total collected oocytes was significantly lower in donor A and B than those in donor C, D and E (82.16 and 70.03% vs. 90.0, 91.78 and 93.57%), respectively (p<0.05). However, number of oocytes per session in donor A, C and E was significantly higher than those in donor B and D ($7.77{\pm}3.26$, $5.85{\pm}2.10$ and $7.03{\pm}2.14$ vs. $4.68{\pm}2.61$ and $5.21{\pm}1.97$ oocytes), but donor A was significantly higher than donor C (p<0.05). Development to blastocyst in donor B, C and E was significantly higher than those in donor A and D (31.0, 25.0 and 25.0% vs. 14.3 and 4.5%), but donor A was not different in donor C and E (p<0.05). Nine out of 10 blastocysts (90.0%) derived from OPU blastocysts were confirmed male embryos that was induced with Y-bearing semen to confirm sex ratio only. Total 96 blastocysts derived from female bearing semen were transferred into synchronized recipients and then confirmed 42 recipients (43.8%) pregnancy rate, 36 offspring (37.5%) and 91.7% female sex ratio (33 female vs. 3 male offspring). Taken together all data, elite dairy female offspring could be produced effectively by in vitro production system between pre-selected x-bearing semen and OPU derived oocytes that would be influential breeder in the breeding of dairy farm to increase effectively elite dairy offspring ratio as well as net income in the dairy farmer.

• 한국동물생명공학회지
• /
• 제34권2호
• /
• pp.106-110
• /
• 2019

Sexed sperm can contribute to increase the profitability of the cow industry through the production of offspring of the craved sex, such as males for meat or females for dairy production. Therefore, the utilization of sexed sperms plays a very important role in the production of offspring of superior cattle. In this study, we examined the pregnancy rates and calves sexing proportion of male and female calves produced using AI, both performed using sexed and conventional sperm. In the result, the conception rates after ET were 73.3% (33/45) sexed semen and 52% (55/104) conventional semen. Thus, the sex ratio for sexed-semen inseminations was 70% (21/30) females for singleton births within a 272 to 292 day gestation interval. The sex ratio for conventional semen was 61% (34/56) females for births. As a result, it is suggested that the use of sex classification sperm will play a very important role in the offspring production of Korean bovine.

• 한국가축번식학회지
• /
• 제11권3호
• /
• pp.218-222
• /
• 1987

This study was conducted using inbred ICR mice to investigate the sex-ratio of preimplantation mouse embryos. For the investigation of sex-ratio of mouse embryos, the karyotype of embryos collected at 70-72, 74-76, 78-80 and 82-84 hr after HCG injection was analyzed by chromosomal analysis. Eight-cell embryos were cultrued up to blastocyst stage, then divided them into three groups(fast-, intermediate- and slow-) according to the blastocoel formation. The sex-ratio was also investigated by chromosomal analysis. 1. The highest apperance of eight-cell and morula was observed at the embryos collected respectively at 66-68 hr(84.6%) and 82-84 hr(79.3%) compared to any other group. 2. The successful rate of embryos sexing at 4-, 8-cell and morula stage were 23.1% (3/13), 42.1%(138/328) and 32.6%(47/141), respectively. The respective sex ratios (female vs male) of 4-, 8-cell and morula were 66.7:33.3, 49.3:50.7 and 39.5:60.5. 3. Of the 476 eight-cell embryos cultured in vitro, 427(89.7%) embryos were developed to the blastocysts and the number of fast-, intermediate- and show-developing embryos were 139, 144 and 144, respectively. 4. Female to male ratios fo fast-, intermediate- and slow-developing group were 23.0:77.0, 55.2:44.8 and 73.8:26.2, respectively. Significantly higher (P<0.05) number of female (48/65;73.8%) was observed in the group of slow-developing embryo than that out of total number of embryos(82/188;43.6%).

• 한국가축번식학회지
• /
• 제20권1호
• /
• pp.53-61
• /
• 1996

This study was carried out to determine effectively the sex of rabbit embryos using H-Y antiserum. H-Y antiserum was obtained from inbred SD strain female rat which was immunized by injection of testis cell of inbred SD strain male rate into its spleen. The titer of antiserum was identified by sperm cytotoxicity test and culture of rabbit embryos with antiserum. The developed or undeveloped embryos were separated by exposure the embryos to the antiserum with H-Y antibody. Developed embryo were transferred to the recipients and sex of offspring were examined. 1. In the sperm cytotoxicity test, the rate of dead sperm showed no difference between two antisera from spleen and testis cell as antigens. It is confirmed that H-Y antibody in antiserum was absorbed by H-Y antigen in male rat spleen cells. 2. When rabbit morulae were exposed to antiserum and complement, the rate of embryos developed or arrested was 51 and 49% respectively and the rate was closely same as natural sex ratio of 50:50%. 3. When rabbit morulae were cultured for 12h in the medium containing antiserum produced by antigen of testis cell, the rate of embryos developed or arrested was 48 and 52% respectively and the rate was closely same as natural sex ratio of 50:50%. 4. Eighty rabbit embryos which were not affected by H-Y antiserum were transferred to four recipients. Two recipients were pregnant and born 13 pups among which 2 (14%) were male and 11 (86%) were female. In conclusion, existence of H-Y antibody in the serum from female rat immunized by injecting testis cell from newborn male rat to the spleen of the female rat was confirmed. When rabbitmorulae were exposed to H-Y antiserum and complement, about a half of embryos were developed to blastocysts. When the rabbit embryos not affected by H-Y antiserum were transferred, the rate of female offspring was 86%. Therefore, it was identified that most of embryos which were not affected by H-Y antiserum were female.