한국재래산양의 임신중 자궁 및 제대혈중의 Progesterone 및 Estradiol 농도에 관한 연구

최상용,박충생 ( S . Y . Choe,C . S . Park ) 한국축산학회 1986 한국축산학회지 Vol.28 No.12

Blood samples were drawn from uterine arteries and veins of 18 pregnant Korean native goats and from the umbilical blood vessels of each of their fetuses by laparotomy at a given stage of gestation and peripartum period, and their serum concentrations of progesterone and estradiol were measured. At 30 days of gestation the progesterone level (15.25 ng/㎖) in uterine arterial serum was similar to that in uterine venous serum. However, during 60 to 120 days of gestation the progesterone levels of uterine venous serum (6.50 to 8.43 ng/㎖) were significantly (P$lt;0.05) lower than those of uterine arterial serum. The progesterone levels in the umbilical arterial or venous serum remained lower than 3.35 ng/㎖ through the gestation period. The estradiol. concentrations in uterine venous serum during the late gestation were significantly (P$lt;0.05) higher than those in uterine arterial serum, but greatly lower than those in umbilical arterial or venous serum. These data suggest that some progesterone is utilized in placenta and estradiol is synthesized in fetoplacental unit during gestation in goats.

한국재래산양의 임신 및 분만전후의 혈중 Steroid Hormone 농도에 관한 연구

최상용,박충생,송우준,김주헌 ( S . Y . Choe,C . S . Park,D . J . Song,J . H . Kim ) 한국축산학회 1986 한국축산학회지 Vol.28 No.6

The peripheral blood was collected from the jugular veins of Korean native goats during gestation and peripartum period. Three goats were selected as samples at every examination designed through the experimental period. The blood samples were centrifuged and stored at -20℃ until hormone assay. The peripheral serum concentration of progesterone was 0.13.03 ng/㎖ at the day of pregnancy and increased greatly to 11.42.44 ng/㎖ at 7 days of pregnancy and thereafter between 9.43 and 14.92 ng/㎖ until 140 days of pregnancy in these 3 goats with an equal gestation period of 145 days, and 8.01±1.67 ng/㎖ at 2 days before parturition, and then declined sharply to 4.60±0.15 ng/㎖, 0.96±0.08 ng/㎖, and (1.37±0.05 ng/㎖ at 1 days and 8 to 0 hours before partiurition and just after parturition, respectively. And this base level of peripheral progesterone concentration was maintained until the Final examination at 6 days after parturition. The peripheral serum concentration of estradiol failed to increase until mid-stage gestation, and thereafter it increased significantly (P$lt;0.05) to 130±25 pg/㎖ at 2 days before parturition and reached a peak of 370±29 pg/㎖ and then declined sharply at 12 hours after parturition. And the base level was maintained until the final examination at 6 days after parturition. There was found a great variation in the peripheral serum level of estradiol between the individuals throughout the gestation period. These results show that the corpus luteum pregnant goats maintain its function normally until 1 to 2 days before parturition and the estradiol may be synthesized in the placenta at increased rate during the late gestation, and its serum level reach to peak just prior to parturition.

산양의 수정란 이식 및 조작기법 개발에 관한 연구 3 . PMSG 와 FSH 를 이용한 산양의 과배란 유기

박충생(C . S . Park),최상용(S . Y . Choe),이효종(H . J . Lee),이지삼(J . S . Lee) 한국축산학회 1991 한국축산학회지 Vol.33 No.4

This study was conducted to investigate the effects of PMSG or FSH treatment with PGF₂α to induce superovulation in Korean native goats. Does were treated with a single s.c. injection of 1,000 IU PMSG on Day 12 or twice daily s.c. injections of a total of 20 ㎎ FSH in decreasing doses over 4 days beginning on Day 12 of the estrous cycle, Estrus was induced by a single i.m. injection of 10 ㎎ PGF₂α 48 hours after the first gonadotropins injection. The does in estrus were mated with intact bucks twice daily 12 hours apart. Ovarian responses and embryo development were observed by laparotomv 72 hours after mating. Mean interval from PGF₂α injection to onset of estrus was significantly(p$lt;0.01) shorter (45.2±7.5 hours) in FSH group than ill PMSG group(64.8±9.6 hours). Duration of estrus, length of estrous cycle and the incidence of short estrous cycle following superovulation were not significantly different between the 2 treatment groups. The mean number of corpora lutea(P$lt;0.01) and ma recovered(P$lt;0.05) were significantly greater for FSH group(13.2 and 9.2) than for PMSG group(5.1 and 3.5). The mean number of trans-ferable embryos kva, 5.9 and 1.9 in FSH-treated and PMSG-treated group. respectively. These results indicate that FSH treatment with PGF₂α could be superior to PMSG treatment with PGF₂α for the induction of superovulation in Korean native goats.

생쥐 8- 세포기 수정란의 핵이식에 의한 복제산자의 생산

최상용(S . Y . Choe),박희성(H . S . Park),이효종(H . J . Lee),박충생(C . S . Park) 한국축산학회 1992 한국축산학회지 Vol.34 No.2

The present study was carried out to develop a technology of cloning mammalian embryos using mouse embryos as a model and to produce cloned offsprings by transfer of reconstituted embryos to recipient females. Single nucleus from eight-cell embryos was transplanted into the enucleated two-cell embryos by micromanipulation and Sendai virus-mediated fusion. The fusion of nuclei with recipient cytoplasm and the development of reconsitituted embryos in vitro as well as in vivo were examined. The results obtained were summarized as follows: A total of 95(59.3%) nuclei from 20 donor embryos of 8-cell stage was injected successfully into the enucleated 2-cell recipient embryos, of which octa-. hepta-, hexa-, penta- and quadruplets were 0. 2, 3, 3 and 12 sets, respectively. The success in nuclei injection was lower(P$lt;0.05) from 8-cell donor embryos than 4-cell or 2-cell donor embryos. Among the embryos injected with nuclei a total of 81(85.2%) embryos were fused successfully with donor embryos of 8-cell stage. From donor embryos of 8-cell stage, 2 hexa-, 2 penta-, 11 quadru- and 5 triplets were fused successfully. A total of 46(39.l%) reconstituted embryos from 8-cell donor nuclei were developed in vitro to blastocysts, of which penta-, quadru- and triplets. twins and singles were 1, 2, 6, 6 and 3 sets, respectively. The development in vitro to blastocysts of the reconstituted embryos was lower (P$lt;0.05) from 8-cell donor embryos than 4- or 2-cell donor embryos. A total of 13(27.l%) cloned live youngs from transfer of cloned embryos using 8-cell donor embryos were produced, of which triplets, twins and singles were 2, 3 and 1 sets, respectively. The percentage of cloned youngs produced from transfer of cloned embryos using 8-cell donor embryos was lower(P$lt;0.05) than 4- or 2-cell donor embryos. The mean number of cloned live youngs produced per 8-cell donor embryo used for nuclei transplantation was 0.81.

산양의 수정란 이식 및 조작기법 개발에 관한 연구 Ⅰ. 산양의 발정유기 및 동기화에 관하여

박충생(C . S . Park),최상용(S . Y . Choe),이효종(H . J . Lee),이지삼(J . S . Lee) 한국축산학회 1989 한국축산학회지 Vol.31 No.1

This experiment was conducted to find out an efficient method for estrus induction and synchronization in goats. Sixty of 83 pluriparous Korean native goats received a single i.m. injection of 3㎎ PGF2α on Days 3 to 12 of the estrous cycle. Remained 23 goats received twice daily i.m. injection of 5㎎ progesterone for 6 or 7 days and a single i. m. injection of 3㎎ PGF2α 1 day before the last injection of progesterone. Serum progesterone concentrations were analyzed by RIA. A single intramuscular injection of 3㎎ prostaglandin F2α(PGE2α) on Days 5 to 12 of the estrous cycle induced estrus in 96% of 50 goats treated, but this treatment on Day 3 to 4 was not effective. Estrus was induced in all of 23 goats injected 3㎎ PGF 2αi.m. 24 hours before the last one of successive injections of 5mg progesterone for 6 or 7 days. The onset of estrus was significantly(P$lt;0.01) earlier in PGF 2α treated goats during Days 5 to 6 of the estrous cycle than those treated on Days 7 to 12. PGF 2α treatment with progesterone delayed significantly (P$lt;0.01) the onset of returning to estrus, compared with the PGF2α injection only during mid-luteal phase of the cycle. Serum progesterone concentration was decreased to a nadir at 24 hours following PGF2α administration on Days 5 to 8 of the cycle, but increased to 2.39±0.66 to 2.69±0.56ng / ml at 48 hours after PGF2α injection on Days 3 to 4. Incidence of short estrous cycle following estrus synchronization by PGF2α with or without progesterone was 26.1 % and 26.0 %, respectively. More effective synchronization of estrus was feasible by progesterone treatment for 6 or 7 days plus PGF2α injection 24 hours prior to the last progesterone administration, compared with a single intramuscular injection of 3㎎ PGF2α alone.

산양의 수정란 이식 및 조작기법 개발에 관한 연구 4 . 생쥐 및 산양 수정란의 분할조작에 의한 일란성 쌍태유기

박충생(C . S . Park),최상용(S . Y . Choe),이효종(H . J . Lee),이지삼(J . S . Lee),박희성(H . S . Park) 한국축산학회 1991 한국축산학회지 Vol.33 No.4

This experiment was conducted to establish a simple technique for bisecting mouse and goat embryos of morula to blastocyst stage and to develop a better culture and transfer system of demi-embryos for the production of identical twins. Mouse morulae or blastocysts and goat blastocysts were easily bisected without pronase treatment, using a microblade fixed to a micromanipulator. Bisected mouse embryos developing normally during culture were 71.4% of a total of 319 morulae and blastocysts. Survival rate of demi-embryos(29.0%) after culture and surgical transfer to recipient mice was comparable to result of intact embryos(26.0%). More transferable embryos (3.5±0.8/donor) were recovered in 7 to 8 days after mating when the does were induced to superovulate by injection of FSH-p in decreasing doses and progesterone priming for 10 days. and this superovulation regimen resulted in very low incidence of short estrous cycle(6.7%). Three kids were produced from 2 of 6 does received intact embryos. Fourteen pairs and one-half of demi-embryos were transferred to 15 recipients. of which one recipient delivered a single female kid.

산양의 수정란 이식 및 조작기법 개발에 관한 연구 5 . 생쥐 및 산양 분할 수정란의 생존성 및 이식 후 수태율의 향상

박충생(C . S . Park),최상용(S . Y . Choe),이효종(H . J . Lee),이지삼(J . S . Lee),박희성(H . S . Park) 한국축산학회 1991 한국축산학회지 Vol.33 No.5

This experiment was conducted to compare different procedures for improvement of viability of embryos after bisection and to investigate some factors affecting development of the bisected embryos. Demi-embryos were successfully produced by micromanipulation of mouse and goat embryos at stages from morula to blastocyst. In mouse, a superior viability(90%) of demi-embryos was achieved by culturing expanded blastocysts after bisection. The highest pregnancy rate(57.1%) and implantation rate(28.2%), which were almost same as the rates of intact embryos. were also achieved by transferring the demi-embryos at this stage after culture for 24 h in vitro. Twenty -eight 3%) of 30 embryos collected from superovulated Korean native goats were successfully bisected, of them 23 demi-pairs were transferred to recipients. Six and 3 does of them were diagnosed pregnant on 21 and 60 days of gestation, respectively. The present result indicates that in goat, hatched blastocysts might be more suitable for successful bisection to produce monozygotic twins than morulae or earlier blastocysts.

산양의 수정란 이식 및 조작기법 개발에 관한 연구 2 . 산양의 분만 및 유산 후의 단발정주기

박충생(C . S . Park),최상용(S . Y . Choe),이효종(H . J . Lee),이지삼(J . S . Lee) 한국축산학회 1991 한국축산학회지 Vol.33 No.4

This experiment was conducted to investigate the incidence of short estrous cycle and control of short cycle in Korean native goats. Abortion was induced by a single i.m. injection of 3 ㎎ PGF₂α at late stage of gestation. Does after parturition or abortion were teased twice daily with vasectornized bucks and behavioral estrus was recorded. Serum progesterone concentration was analysed by RIA. Mean post-partum or post-abortion interval to first estrus was shortest as 11.9 days in PGF₂α-aborted does compared to 22.1 days in does isolated from their kids within 7 days after parturition and 26.8 days in suckling does. Duration of this first standing estrus was not significantly different among groups. Four limes daily injections of 25 ㎍ Gn RH to does for Day 3 to 5 of the first estrous cycle following parturition or abortion ruduced significantly(p$lt;0.0l) the incidence of short estrous cycle to 38.5% compared to 80.0% in control group of does. Mean concentration of serum progesterone in does showing short estrous cycle was found to be basal level at estrual phase but considerably high level up to 1.06 ㎎/㎖ on Day 3 to 4 of the cycle. These results indicate that the short estrous. cycle may he resulted from the premature luteal regression and GnRH treatment during early luteal phase of the estrous cycle can partly prolong the short lifespan of corpora lutea.

재래산양의 번식의 계절성 및 분만과 유산후의 발정재귀

송우준,박충생,최상용,최경문 ( D . J . Song,C . S . Park,S . Y . Choe,K . M . Choe ) 한국축산학회 1984 한국축산학회지 Vol.26 No.4

To determine the seasonal variations in breeding activity and return to estrus after parturition with or without suckling kids or induced abortion in Korean native goats, thirty primiparous goats of about 2 year old were barn-housed at Gyeongsang National University Farm (N.L.: 35°1`) and allowed with daily supplements of about 200g and liberal feeding of grasses through the experimental period from November, 1982 to October, 1983. The goats were checked twice daily in 12 hours interval for the presence of estrus. The goats were checked twice daily in 12 hours interval for the presence of estrus. The goats were exposed to vasectomized bucks for 30 minutes and the successful mating was identified as a standing estrus. Seasonal patterns for percentage of goats showing estrus behaviors and return to estrus following induced abortion and normal parturition with or without suckling kids were examined. The results obtained were as follows: The monthly percentage of goats showing; more than one estrous behaviour to all the experimental goats available for breeding was highest (94 - 100%) in October to February, lowest (17 - 22%) in July to August, and not varied greatly (58 - 76%) between the other months. These data suggest that Korean native goat may be a typical breed having a very short non-breeding season or showing less fluctuation in breeding activity through the year, compared with other breeds in the temperate region. The successful abortions were induced in all the 5 gnats of 2 - 4 months of pregnancy 30 to 40 hours after intramuscular injection of 3㎎ of PGF₂α Of ten goats which kidded normally, 5 goats were suckled for 60 days and the other 5 goats were separated from their kids 4 days after kidding. The average return interval to estrus after kidding or induced abortion was 12.2±1.2 days, 27.2±7.2 days and 33.0±3.2 days in the group of induced abortion, parturition with and without suckling, respectively. There were significant differences in return period to estrus between induced abortion and parturition with (P$lt;0.05) or without suckling (P$lt;0.01). The short estrous cycles were found after first estrus in all the goats preceded by induced abortion and parturition with suckling, and in the 3 of 5 goats preceded by parturition without suckling.

재래산양의 단발정주기중 혈청 Progesterone 및 Estradiol - 17β 의 수준의 변화

송우준,박충생,최상용 ( D . J . Song,C . S . Park,S . Y . Choe ) 한국축산학회 1985 한국축산학회지 Vol.27 No.10

The peripheral blood was collected from 6 Korean native goats which showed a short estrous cycle from 5.5 to 7.0 days. The serum levels of progesterone and estradiol-17β were determined at the interval of 12 hours through the estrous cycle. Using a vasectomized buck the estrous behaviours of the goats were checked twice a day. The average levels of serum progesterone were found lower than 0.02ng/㎖ at Day 0 before and after the short cycle, and increased to 0.14ng/㎖ at Days 2 and 3, and 1.15ng/㎖ (0.57-1.64ng/㎖) at Days 4 and 5. The levels of serum estradiol-17β through the short estrous cycle was fluctuated in a similar pattern to normal estrous cycle. These data suggest that the short estrous cycle may be resulted from the early regression of the premature corpus lutea.