• Title/Summary/Keyword: 수정란 이식

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Comparative Evaluation on Sperm Parameter of Transgenic Pigs with General Pigs (형질전환 돼지의 정자와 일반돼지의 정자성상에 대한 비교평가)

  • Park, Sang Hyoun;Lee, Gunsup;Lee, Joo Yung;Kim, Kyung Woon;Byun, Sung-June;Ock, Sun A;Hwang, Seongsoo;Yang, Hyeon;Woo, Jae-Seok;Oh, Keon Bong
    • Journal of Embryo Transfer
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    • v.32 no.3
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    • pp.227-233
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    • 2017
  • Pig has been known to be one of the most feasible animals as a bioreactor to produce pharmaceuticals in milk and as a mediator in xenotransplantation research. Previously, we generated transgenic pigs for both purposes, which were expressing Factor 8, vWF, hTPA, and hEPO in milk, along with expression of MCP at GalT gene locus ($GalT^{-MCP/-MCP}$) as well as expressing MCP at GalT gene loci with CD73 expression ($GalT^{-MCP/+}/CD73$). In this study, we performed comparative analyses of sperm parameters between wild type male (WT) pig and those transgenic males to examine the effects of transgenes integrated into the pigs on motility, morphology, viability, and acrosome integrity of the spermatozoa. Our results showed that the rates of actively motile spermatozoa of WT, Factor 8, vWF, hTPA, hEPO, $GalT^{-MCP/+}/CD73$, and $GalT^{-MCP/-MCP}$ pigs were 85.0%, 83.3%, 82.5%, 83.3%, 82.5%, 77.5%, and 78.7%, respectively. Whereas, the rates of morphologically normal spermatozoa of WT, Factor 8, vWF, hTPA, hEPO, $GalT^{-MCP/+}/CD73$, and $GalT^{-MCP/-MCP}$ pigs were 90.0%, 80.0%, 80.0%, 83.3%, 85.0%, 91.8%, and 80.8%, respectively. In addition, the viability in spermatozoa of WT, Factor 8, vWF, hTPA, hEPO, $GalT^{-MCP/+}/CD73$, and $GalT^{-MCP/-MCP}$ pigs were 93.9%, 82.4%, 89.9%, 83.9%, 87.4%, 92.8%, and 83.6%, respectively. The rates of spermatozoa with normal acrosome integrity in WT, Factor 8, vWF, hTPA, hEPO, $GalT^{-MCP/+}/CD73$, and $GalT^{-MCP/-MCP}$ pigs were 98.1%, 98.6%, 98.6%, 98.7%, 98.1%, 99.5%, and 95.1%, respectively. There were no significant differences in motility, morphology, viability, and acrosome integrity of the spermatozoa among WT, Factor 8, vWF, hTPA, and hEPO, $GalT^{-MCP/+}/CD73$, and $GalT^{-MCP/-MCP}$ pigs. These mean that neither random integration nor targeted integration of the transgene into chromosome of pig effect on characteristics of spermatozoa. Ultimately, the transgenic male pigs subjected in this study could apply to propagate their progenies for production of human therapeutic proteins and advancing the xenotransplantation research.

Carbohydrate Metabolism in Preimplantation Stage Embryos and the Role of Metabolites (착상전 초기 배아에서 탄수화물 대사와 그 대사물의 역할)

  • Cheon, Yong-Pil
    • Development and Reproduction
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    • v.12 no.1
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    • pp.19-30
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    • 2008
  • Proper development of fertilized oocyte to blastocyst is a key step in mammalian development to implantation. During development of preimplantation embryos, the mammalian embryo needs supply the energy substrate for keep viability. Usually mammalian oocyte get substrate especially energy substrate from oviduct and uterus, because it does not store much substrate into cytoplasm during oogenesis. Carbohydrates are known as a main energy substrate for preimplantation stage embryos. Glucose, lactate and pyruvate are essential component in preimplantation embryo culture media and there are stage specific preferences to them. Glucose transporter and $H^+$-monocarboxylate cotransporter are a main mediator for carbohydrate transport and those expression levels are primarily under the control of intrinsic or extrinsic factors like insulin and glucose. Other organic substances, amino acids, lipids and nucleotides are used as energy substance and cellular regulation factor. Though since 1960s, successful development of fertilized embryo to blastocyst has been accomplished with chemically defined medium for example BWW and give rise to normal offspring in mammals, the role of metabolites and the regulation of intermediary metabolism are still poorly understood. Glucose may permit expression of metabolic enzymes and transporters in compacting morula, capable of generating the energy required for blastocyst formation. In addition, it has been suggested that the cytokines can modulate the metabolic rate of carbohydrate in embryos and regulate the preimplantation embryonic development through control the metabolic rate. Recently we showed that lactate can be used as a mediator for preimplantation embryonic development. Those observations indicate that metabolites of carbohydrate are required by the early embryo, not only as an energy source, but also as a key substrate for other regulatory and biosynthetic pathways. In addition metabolites of carbohydrate may involve in cellular activity during development of preimplantation embryos. It is suggested that through these regulation and with other regulation mechanisms, embryo and uterus can prepare the embryo implantation and further development, properly.

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Prediction of Parthenogenetic Developmental Potential by Polar Body Extrusion and First Cleavage on In Vitro Maturation and Development of Porcine Follicular Oocytes (돼지 난모 세포의 Ethanol 처리에 의한 단위 발생에 있어서 극체 방출란과 분할란 선별에 따른 배발달율 비교)

  • Kim, H.J.;Cho, S.R.;Choe, J.Y.;Choi, S.H.;Han, M.H.;Son, D.S.;Lee, S.S.;Sang, B.D.;Ryu, I.S.;Kim, I.C.;Kim, S.J.;Kim, I.H.;Kim, S.K.
    • Journal of Embryo Transfer
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    • v.22 no.2
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    • pp.121-126
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    • 2007
  • The objective of this study was carried out to examine the selection effects of in vitro matured porcine follicular oocytes with polar body extrusion and early cleavage as non-invasive marker to know the developmental competence in advance. The porcine oocytes matured for 48 h were examined the polar body extrusion. The examined oocytes were matured for additional $16{\sim}18h$ and activated with 7% ethanol and cultured in $5{\mu}g/ml$ cytochalasin B for 5 h for diploid formation. The treated oocytes were cultured and examined the cleavage after 48 h and continued culturing for 5 days. The oocytes of 21.9% were discarded in morphological selection and 32.1% oocytes were discarded by failure of first polar body extrusion. The selected oocytes were matured and activated and then after 48 h the cleavage rates were examined. In morphologically selected oocytes, 15.8% oocytes were not cleaved and 52.6% oocytes were normally cleaved and 31.6% oocytes were hyper-cleaved over 8-cell stage. However in the first polar body extruded oocytes, 7.1% oocytes were not cleaved and 73.1% oocytes were normally cleaved and 19.8% oocytes were hyper-cleaved. The morphologically selected embryos that not cleavage-selected were developed in 16.7% up to blastocyst and the morphologically selected and cleavage-selected embryos were developed in 31.7%. The polar body extruded oocytes that were not carried out cleavage selection were developed in 39.0% and the polar body extruded and cleavage-selected embryos were developed 49.0%. The first cleavage timing was examined with 12 h interval after activation. In $0{\sim}12,\;12{\sim}24,\;24{\sim}36,\;and\;36{\sim}48h$ intervals, 4.1%, 68.6%, 19.1%, and 2.3% oocytes were cleaved and 5.9% oocytes were not cleaved until 48 after activation. The cleaved oocytes in each interval were cultured and developed upto blastocyst with 0, 39.1, 9.5, and 0%, respectively. This results suggests that polar body extruded and cleaved at $12{\sim}36h$ embryo has higher developmental potential than the others.

Phenotypic Correlation between Carcass Traits and Serum Profiles taken Before and After Slaughter of Hanwoo Bulls and Steers (가축에서 시기별 혈액 성분과 도체 형질에 대한 표현형 상관에 관한 연구)

  • Jeon G. J.;Choy Y. H.;Cho K. H.;Kim M. J.;Kim H. C.;Choi J. G.;Lee C. W.;Hwang J. M.;Kim J. B.
    • Journal of Embryo Transfer
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    • v.20 no.3
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    • pp.239-253
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    • 2005
  • Serum concentrations of Hanwoo steers and bulls as possible indicators of beef quality were analyzed to estimate their correlations with carcass traits. Blood samples were taken 2 months and right before shipping to abattoir and at the time of slaughter. And phenotypic correlation coefficients between serum concentrations and carcass traits were estimated. Beef yield index of steers was positively correlated with serum concentrations of total Protein (0.23), albumin (0.26), and calcium (0.31). But it was negatively co..elated with BUN (-0.30). Loin eye area was positively correlated with BUN (0.17) or with globulin (0.16). Back fat thickness was positively correlated with BUN (0.42) and inorganic phosphorus (0.20) being negatively correlated with total protein (-0.23), albumin (-0.33) and calcium (-0.33). Marbling score in the scale of 1 (scarcely marbled) through 9 (extremely marbled) was positively correlated with BUN (0.28) and negatively with IGF-I and calcium concentrations. Phenotype correlation coefficient of loin eye area with total protein concentration in the serum taken from steers right before shipment was estimated to be -0.16 and that with BUN was estimated to be -0.15. Serum concentrations of IGF, glucose, creatinine and on organic phosphorus from steers measured right before shipment were negatively correlated with respective correlation coefficient estimates as -0.21, -0.21, -0.19 and -0.18. Marbling score was negatively co..elated with serum creatinine (-0.16) measured at that time. Beef yield index of steers was positively correlated (0.31) with age adjusted calcium concentration in the serum taken at the time of slaughter. Correlation between body weight and BUN at slaughter was 0.17 At slaughter, loin eye area was negatively correlated with albumin (-0.19) and back fat thickness was also negatively correlated with age adjusted calcium concentration (-0.38). Marbling was negatively correlated with age adjusted calcium concentration(-0.17). Serum concentrations of testosterone, calcium and inorganic phosphorus taken in 2 months before slaughter were negatively but highly correlated with yield index(0.71, 0.67 and -0.71), respectively. Body weight at slaughter was positively was negatively correlated (0.67) with calcium level while dressing percentage was negatively (-0.69) correlated with serum glucose concentration, 2 months prior to slaughter. Correlation coefficients between back fat thickness and cortisol, between back fat thickness and inorganic phosphate were both positive (0.29 and 0.69). Marbling score was negatively correlated with creatinine (-0.81) and positively with BUN (0.87). Body weight loss during shipping was positively correlated with albumin and inorganic phosphate (0.77, 0.83). Yield index of bulls was positively correlated with serum testosterone concentration (0.66). Dressing percentage was positively and highly correlated with globulin (0.73). Back fat thickness of bulls, however, was negatively correlated with testosterone (-0.60). Loin eye area of bull carcasses was positively correlated with testosterone (0.40). Mar-blaine was negatively co..elated with creatinine (-0.55). Yield index of bulls and age adjusted HDLC concentration at slaughter was negatively correlated (-0.71). Dressing percentage of bulls was positively and highly correlated with globulin concentration (0.70). Back fat thickness was also positively correlated with HDLC (0.69) in the serum taken at slaughter. Correlation coefficients between carcass weight and triglyceride, between loin eye are and testosterone and between marbling score and creatinine or glucose were 0.51, -0.91 and -0.58, respectively.

Effect of $PGF_2a+PGF_2a+CIDR$ Program on Estrous Response in Holstein with Varying BCS in Early Postpartum (분만후 젖소에 있어서 $PGF_2a+PGF_2a+CIDR$ Program 적용에 의한 발정유기시 BCS의 영향)

  • Baek K. S.;Park S. J.;Park S. B.;Kim H. S.;Lee H. J.;Lee W. S.;Jeon B. S.;Ahn B. S.;Kim J. G.;Jeong G. Y.;Son J. K.
    • Journal of Embryo Transfer
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    • v.20 no.3
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    • pp.279-287
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    • 2005
  • This study was carried out to investigate resumption of ovarian cyclicity and effect of BCS on estrous response by treatment of $PGF_2a+PGF_2a+CIDR$ program on day 40 postpartum in lactating dairy cow. First $PGF_2a$ was given on day 40 postpartum, second $PGF_2a$ was given 14 days apart to cows not-responded to 1st $PGF_2a$ and then CIDR was inserted for 7 days after 5 days in cows not-responded to 2nd $PGF_2a$. The $42.9\%$ of the cows showed more than 1 ng/mL milk progesterone concentration within 10 to 30 days postpartum. About $19\%$ of the cows exhibited more than 1 ng/mL milk pro-gesterone concentration between 31 to 50 days postpartum. However $38.1\%$ of the cows have not shown more than 1 ng/mL milk progesterone up to 50 days postpartum. Estrous response to the treatment of 1 st $PGF_2a$ and 2nd $PGF_2a$ was $47.5\%$ and $52.4\%$, respectively. Combination of 1 st $PGF_2a$ and 2nd $PGF_2a$ was $75\%$ and combination of 1st $PGF_2a$+2nd $PGF_2a$+CIDR was $87.5\%$. Estrous response to the treatment of $PGF_2a+PGF_2a$ program was $61.5\%$ in cows with less than 2.50 BCS and $81.5\%$ in cows with 2.75${\~}$3.50 BCS. Estrous response to the treatment of CIDR was $40\%$ in cows with less than 2.50 BCS and $80\%$ in cows with 2.75${\~}$3.50 BCS. Estrous response to the treatment of PPC on day 40 postpartum was $76.9\%$ in cows with less than 2.50 BCS and $96.3\%$ in cows with 2.75${\~}$3.50 BCS.

Relationship between Vaginal Cytology and Reproductive Hormone during the Estrous Cycle and Optimal Mating Time in Beagle Dogs (비글개에서 발정 주기 및 교배 적기 동안 질세포상과 번식 호르몬의 관계)

  • Lee K.C.;Kang H.G.;Cheun H.M.;Kim I.H.
    • Journal of Embryo Transfer
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    • v.21 no.2
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    • pp.109-119
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    • 2006
  • This study was conducted to examine relationship between vaginal cytology and reproductive hormones during the estrous cycle and to provide basic data to estimate for ovulation time and optimal mating time in 6 beagle dogs The duration of proestrus, estrus and diestrus were $8.5{\pm}1.4,\;10.0{\pm}1.4\;and\;54.0{\pm}2.8$ days at pregnant respectively, and $7.9{\pm}2.1,\;9.5{\pm}0.7\;and\;62.0{\pm}11.3$ days at non-pregnant respectively. The duration of interestrous intervals were $246.2{\pm}24.5$ days at pregnancy, and $175.3{\pm}34.5$ days at non-pregnancy. The duration of interestrous intervals at pregnancy was longer than that of non-pregnancy. A characteristic features of vaginal cytology during the estrous cycle were the high proportion of superficial cell, anuclear cell and erythrocyte in proestrus and estrus, parabasal cell, small intermediate cell and leukocyte in diestrus, and parabasal cell and small intermediate cell in anestrus, respectively. Cornification index (CI) in proestrus and estrus were significantly higher than that of CI in diestrus and anestrus. Plasma progesterone concentration was below 1.0 ng/ml at the first day of vulval bleeding at pregnancy and non-pregnancy, and then it was above 2.0 ng/ml at Day -2 in all bitches. When plasma progesterone concentration was first increased above 4.0 ng/ml, it was the second day after the first day of male acceptance. Plasma progesterone concentration showed above 40 ng/ml on Day $20{\sim}22$ in all bitches, and then it was gradually decreased until Day 35. Plasma progesterone concentration at pregnancy was higher than that of non-pregnancy from Day 35 to Day 63. Plasma estradiol-$17\;{\beta}$ concentration was above 9.0 pg/ml at the first day of vulval bleeding, and it showed 26.4 pg/ml on Day -2. When it was timed from the first day of male acceptance (Day 0), plasma estradiol-$17{\beta}$ concentration showed a peak on Day 0 and plasma progesterone concentration was first increased above 4.0 ng/ml on Day 2 which was the third day after plasma estradiol-$17{\beta}$ peak. CI was first increased above 80 and 90% on Day -1 and Day 1, respectively. CI was maintained above 80% from Day -1 to Day 8 (10 days) and above 90% from Day 1 to Day 6 (6 days), respectively. CI was maintained above 80% from Day 0 to Day 8 (9 days) and above 90% from Day 1 to Day 6 (6 days), respectively. Plasma progesterone concentration was first increased above 4.0 ng/ml on the second day after the day which CI was first increased above 90%. In conclusion, beagle bitches ovulated on the second day after the day which CI was first increased above 90% and on the day which plasma progesterone concentration was first increased 4.0 ng/ml, and it was estimated that the optimal mating time was the day which the second day after CI was first increased above 90% and plasma concentration was between $2{\sim}25ng/ml$. The measurement of plasma progesterone was used to determine of and accurate ovulation time and the optimal mating time, but vaginal cytology is low-priced and simple method to estimate estrous cycle, optimal mating time and ovulation time.

Effect of rbST Administrations at Artificial Insemination on Conception and Parturition Rates in Hanwoo (한우 인공수정시 rbST 투여가 수태 및 분만율에 미치는 영향)

  • Han M. H.;Choi S. H.;Choi Y. H.;Kim H. J.;Cho S. R.;Choi C.Y.;Ryu I. S.;Son D. S.;Yeon S. H.;Woo J. S.;Kweon U. G.;Yoon K. Y.;Chang B. S.
    • Journal of Embryo Transfer
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    • v.20 no.2
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    • pp.177-184
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    • 2005
  • This study was conducted to investigate the effects of recombinant bovine somatotropin (rbST) injection on conception and parturition rates in normal or repeat breeding Hanwoo. We treated 462 cows containing 79 repeat-breeding cows of multiparous and allocating 5 treatment groups. Treatment 1 (T1) was injection of 2ml saline (for pseudo treatment), T2 was one injection of rbST 250mg into the tailhead region at the estrus, T3 was twice injection of rbST 250mg both at the time of insemination and again 10 to 14 day later, T4 was once injection of rbST 500mg at insemination and T5 was twice injection of 500mg rbST both at the time of insemination and again 10 to 14day later respectively. In rbST treated groups, timed artificial inseminations (TAI) were performed fellowing estrus synchronization. 100 us GnRH was injected into the scapula region on Day 0, 25mg $PGF_2{\alpha}$ was injected on Day 7 for degeneration of corpus luteum (CL) and 100ug GnRH was injected for inducing the synchronization. The results are as fellows; When normal Hanwoo were inseminated once with rbST administration, the pregnancy rate of T2 $(67.5\pm18.48\%)$ were higher than control $(52.4\pm9.72\%)$, while the pregnancy rate of T4 $(63.3\pm5.77\%)$ were significantly higher (p.<0.05) than control $(39.3\pm12.89\%)$ in repeat breeder Hanwoo. The parturition rates of normal Hanwoo were no differences among the treatments but were significant different in repeat breeder Hanwoo (p<0.05). When the estrous was induced by Ovsynch and inseminated once with rbST administration, the pregnancy rates of T2 was $12.5\%$ higher than control in normal Hanwoo, T4 $(80.0\%)$ was highest among the treatments (p<0.05) in repeat breeder Hanwoo. When normal Hanwoo were inseminated once with rbST administration, the pregnant period was $282.7\~284.8$ days and the body weight was $25.1\~25.9kg$, there were no difference among the treatments. The ratio of sex was almost same without T4 (male vs. female=18:9). In repeat breeder Hanwoo, pregnant period was 280.4~289.3 day and body weight was $23.0\~26.6kg$, it had no difference among the treatments. The sex ratio were similar to normal Hanwoo except T4 (M : F=2 : 8). In conclusion, the pregnancy and parturition rate by once insemination could be improved by the administration of rbST 250mg in normal Hanwoo or 500mg in repeat breeder Hawoo.

Relationship between Estrous Expression, Body Condition Score (BCS) and Transferable Embryos Hanwoo Donors (한우 공란우의 발정발현율, 신체 충실 지수(BCS)와 이식가능 수정란과의 관계)

  • Son, Jun-Kyu;Choe, Chang-Yong;Cho, Sang-Rae;Lim, Hyun-Joo;Park, Seong-Jin;Baek, Kwang-Soo;Kim, Sang-Bum;Kwon, Eung-Gi;Jung, Yeon-Sub;Bok, Nan-Hee;Son, Dong-Soo
    • Reproductive and Developmental Biology
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    • v.35 no.3
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    • pp.349-353
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    • 2011
  • The objective of this study was to investigate the relationship between estrous expression, body condition score (BCS), blood urea nitrogen (BUN) and number of transferable embryos for the purpose of improving reproductive performance in blood of Hanwoo donors. Sixty, at random stages of the estrous cycle, received a CIDR. Four days later, the animals were superovulated with a total of 28AU FSH (Antorin, 2AU=1 ml) administered twice daily in constant doses over 4 days. On the 3th administration of FSH, CIDR was withdrawn and 25 mg PGF2 ${\alpha}$ was administered. Cows were artificially inseminated twice after estrous detection at 12 hr intervals. The cows received 100 ${\mu}g$ GnRH at the time of 1nd insemination. Embryos were recovered 7 or 8 days after the 1st insemination. The estrous inducement rate and estrous expression rate were significantly lower for cows with BCS below 2.25 than for cows with BCS above 2.25. There was 50.0% of rate of mounting in cows with BCS below 2.25 whereas the rate of mounting was markedly increased in cows with BCS above 2.25 (94.1% and 89.5% for BCS 2.25~2.75 and BCS above 2.75 cows, respectively). Cows with BCS <2.25, 2.25~2.75 and ${\geq}$2.75 had number of transferable embryos of $4.5{\pm}0.7$, $5.9{\pm}1.8$ and $5.6{\pm}2.3$ respectively.

Relationship between Transferable Embryos and Blood Urea Nitrogen, Glucose and Total Cholesterol Concentration in Hanwoo Donors (한우 공란우 이식기능 수정란수와 혈액내 요소태질소, 포도당 및 총콜레스테롤 수준과의 관계)

  • Son, Jun-Kyu;Choe, Chang-Yong;Cho, Sang-Rae;Lim, Hyun-Joo;Park, Seong-Jai;Baek, Kwang-Soo;Kim, Sang-Bum;Kwon, Eung-Gi;Jung, Yeon-Sub;Bok, Nan-Hee;Son, Dong-Soo
    • Reproductive and Developmental Biology
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    • v.35 no.3
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    • pp.335-339
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    • 2011
  • The objective of this study was to investigate the relationship between concentration of urea nitrogen, glucose, cholesterol and number of transferable embryos for the purpose of improving reproductive performance in blood of Hanwoo donors. Fifty five, at random stages of the estrous cycle, received a CIDR. Four days later the animals were superovulated with a total of 28AU FSH (Antorin, 2AU=1 ml) administered twice daily in constant doses over 4 days. On the 3th administration of FSH, CIDR was withdrawn and 25 mg $PGF_2$ ${\alpha}$ was administered. Cows were artificially inseminated twice after estrous detection at 12 hr intervals. The cows received 100 ${\mu}g$ GnRH at the time of 1nd insemination. Embryos were recovered 7 or 8 days after the 1st insemination. Cows with BUN < 10, 11~18 and ${\geq}$19 mg/dl had number of transferable embryos of $4.32{\pm}1.3$, $5.8{\pm}1.8$ and $4.7{\pm}2.1$ respectively. The mean numbers of total ova from < 10 and 10${\leq}$ of corpora lutea(CL) was 8.9 and 14.3, respectively. The number of transferable embryos differed between < 10${\leq}$ CL was 4.8 and 5.6, respectively.

Artificial Spawning, Larval and Spat Developments of the Bay Scallop, Argopecten irradians (해만가리비, Argopecten irradians의 인공산란과 유생 및 치패의 발생)

  • Oh, Bong-Se;Jung, Choon-Goo;Kim, Sook-Yang
    • The Korean Journal of Malacology
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    • v.19 no.1
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    • pp.19-24
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    • 2003
  • Artificial spawning, larval and spat developments of the bay scallop, Argopecten irradians, which was transplanted from China on 16 August 1996, were investigated monthly until August 1997 in the Deukyang Bay, Jangheung-gun, Jeollanam-do, Korea. Sufficient amount of cultured microalgae supplemented seawater were supplied as food (6 kinds of phytoplankton) for fully grown adult individuals at 17.1-23.2$^{\circ}C$ for 44 days. A total of 45,320,000 eggs were spawned by way of 2 times of artificial spawning inductions such as exposure stimulus to the air and thermal shock (with water temperature) on 29 January and 31 January in 1997. Artificially fertilized eggs were developed to D-shaped larvae (77.5 ${\times}\;63.8\;{\mu}m)$ and metamorphosed to larvae (191.8 ${\times}\;181.2\;{\mu}m)$ 181.2 m) in the attached larval stage on the collectors. A total of 110,000 spats (average 3.04 mm in shell length) were produced at 22.8-26.3$^{\circ}C$ and 31.0-34.4 psu in the indoor rearing tank from 14 February through 7 May in 1997. In case of Argopecten irradians, if the attached larvae in the attachment stage are detached from the collector, they could not live. Accordingly, it is assumed that survival (%) of the attached larvae of A. irridians showed very low because of weak power attached to the collector due to the small number of the byssuses of the attached larva, not the short attachment period by the byssus as seen in other scallops such as Argopecten balloti.

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