• Asian-Australasian Journal of Animal Sciences
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• 제20권4호
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• pp.461-465
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• 2007

Porcine Endogenous Retroviruses (PERVs) are a major concern in relation to xenotransplantation. Previous research indicated that PERVs are present at about 50 copies in the pig genome and their chromosomal insertion sites are different among pig breeds. We examined nine Korean native pigs and seven Asian Wild Boars for the presence of a PERV-A at SSC 1q2.4 and a PERV-B at SSC 7p1.1-2 previously reported in a Large White pig. The PERV-B at locus 7p1.1-2 displayed insertional variability in Korean native pigs and Asian Wild Boars. Using the primers for the PERV-A at 1q2.4 from Large White pig, we only can amplify an unclassified 798 bp sequence, which showed insertional variability only in Korean native pigs. This study indicates that there are differences within and between Asian and European pigs in PERV insertions and suggests that selection could generate PERV-free lines of pigs more suitable for xenotransplantation.

• Reproductive and Developmental Biology
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• 제33권4호
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• pp.195-202
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• 2009

Abnormal development and fetal loss during the post-implantation period are key concerns in the production of cloned animals by somatic cell nuclear transfer (SCNT). We hypothesized that the problems in cloned porcine offspring derived from SCNT are related to interactions between the conceptus and the endometrial environment. In the present study, we investigated expression patterns in the formation of placenta-related genes (Cdx2 and GATA6) in whole in vivo normal porcine embryos (from single cell to blastocyst) and each tissue of a normal fetus at Days 25, 35 and 55 by quantitative mRNA expression analysis using real-time PCR. The expression of Cdx2 and GATA6 mRNA increased to around the blastocyst stage. These genes were gradually decreased from the peri-implantation to post-implantation stage. Moreover, we examined the expression patterns of Cdx2 and GATA6 in Day 35 normal and SCNT cloned fetuses by the same methods. And, the level of Cdx2 and GATA6 gene expression in the extraembryonic tissue of SCNT was significantly higher than that of control tissues. From the present results, it can be postulated that the aberrant expression of Cdx2 and GATA6 genes in the endometrial and extraembryonic tissues at pre- and peri-implantation stages may be closely related to the lower efficiency of animal cloning.

• 한국동물생명공학회지
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• 제35권3호
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• pp.258-264
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• 2020

This study investigated the effect of variation in the number of somatic-cell-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.

• Reproductive and Developmental Biology
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• 제31권3호
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• pp.139-143
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• 2007

본 연구는 체세포를 이용하여 생산된 복제 한우 수소의 번식능력을 검토하기 위해 실시하였다. 복제 한우 수소(C-38 및 C-39) 또는 일반 한우 종모우로부터 정액을 채취하여 정자의 수 및 동결 전 후의 생존성 등을 살펴보았으며, 정자의 운동성 등은 computer assisted sperm analysis(CASA)를 이용하여 측정하였다. 또한, 이들의 수정 능력을 확인하기 위하여 체외수정과 인공수정을 각각 실시하였다. 정액 성상에서는 복제 수소들과 일반 종모우 간에 정액의 양, 정자의 농도 및 동결융해 후의 생존성 등에서 차이가 나타나지 않았다. CASA를 이용한 분석에서 운동성, 곡선 운동 속도(VCL), 직선운동 속도(VSL) 및 평균 진행 속도(VAP) 등은 복제 수소의 정액이 일반 종모우의 정액에 비하여 유의적으로 높았다 (p<0.05).체외수정에 따른 수정란의 분화율 및 배반포로의 발달율은 복제 수소와 일반종모우 간에 차이가 나타나지 않았다. 복제소 정액(C-38)을 이용하여 인공수정을 한 5두의 체세포 복제 대리모에서 암 수 각각 한 두씩의 건강한 복제 후대 송아지 2두를 생산하였다. 이상의 결과를 종합하여 보면, 실험에 공시된 복제 수소 개체간의 차이가 나타나기는 하였지만, 복제 수소는 정액 성상과 정자의 운동성 등에서 일반 종모우와 차이가 없었으며, 또한 인공수정을 통해 송아지를 생산함으로써 정상적인 번식능력이 있음을 확인하였다.

• 농업과학연구
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• 제43권4호
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• pp.575-580
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• 2016

This study was performed to determine whether supplementation of tauroursodeoxycholic acid (TUDCA), an endoplasmic reticulum (ER) stress inhibitor, during vitrified cryopreservation enhances the development of frozen mouse embryos. Mouse 8-cell stage embryos were collected and exposed to a cryoprotectant solution containing TUDCA or TM (tunicamycin, an ER stress inhibitor) at room temperature and stored in liquid nitrogen following vitrification. The final concentration of TUDCA or TM was $50{\mu}M$. The survival and development rates of mouse 8-cell stage embryos exposed to TUDCA- or TM-containing solutions at room temperature or stored in liquid nitrogen following vitrification were measured. There were no significant differences in survival rate and blastocyst formation rate among control, TUDCA, and TM groups after embryos were exposed to vitrification solutions at RT. When mouse 8-cell stage embryos were treated with TUDCA or TM and then stored in liquid nitrogen, the survival rates of control and TUDCA groups were significantly higher than for the TM group. Blastocyst formation rate of the TUDCA group following in vitro culture was significantly higher than that in control or TM groups. The TM group showed a lower (p < 0.05) blastocyst formation rate than the other two groups. Our results indicate that TUDCA supplementation during cryopreservation of mouse embryos could enhance their development capacity.

• Reproductive and Developmental Biology
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• 제31권4호
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• pp.227-233
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• 2007

This study was conducted to examine the mRNA expression of apoptosis-related and imprinted genes and methylation pattern of the differentially methylated region (DMR) of H19 gene in day 35 of SCNT pig fetuses. The day 35 of natural mating (control) or cloned (clone) pig fetuses were recovered from uterus. Endometrium from dam and liver from fetus were obtained, respectively. mRNA expression was evaluated by real-time PCR and methylation pattern was analyzed by bisulfite sequencing method. The Bcl-2 mRNA expression in clone was significantly lower than that of control (p<0.05). The mRNA expression of H19 gene in both endometrium and liver was significantly higher in clone than that of control, respectively (p<0.05). The level of IGF-2 mRNA in liver of clone was significantly lower than that of control (p<0.05), whereas the mRNA expression of IGF2-R gene in liver of clone was significantly higher than that of control (p<0.05). The DMR of H19 was lower methylation pattern in clone than that of control. These results suggest that the aberrant mRNA expression of apoptosis-related and imprinted genes and the lower DMR methylation pattern of imprinted gene may be closely related to the inadequate fetal development of cloned fetus.

• Asian-Australasian Journal of Animal Sciences
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• 제17권8호
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• pp.1076-1079
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• 2004

Antibiotics are common additives in culture media during in vitro embryo development, but their effects on oocyte maturation in vitro have not been tested. The effects of penicillin, streptomycin and gentamicin on the maturational competence and subsequent development potential of goat follicular oocytes were examined after parthenogenetic activation in vitro. Maturation rates at 24 h after in vitro maturation, and parthenogenetic development at 48 h after activation, were evaluated by observing the protruding first polar body and the 4 cell stage cleavage, respectively. When streptomycin was present in the maturation medium, the percentages of matured oocytes 24 h after activation were significantly (p<0.01) lower than those from the other groups (42.5-45.7% vs. 69.1-73.8%). Penicillin and gentamicin treatment did not affect the maturation rates or the percentages reaching the 4 cell stage 48 h after activation. There was no significant difference in cleavage rates among the different antibiotic treatments 48 h after activation. Therefore, streptomycin suppresses the in vitro maturation of immature goat oocytes, but does not influence their subsequent development.

• Reproductive and Developmental Biology
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• 제36권4호
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• pp.249-254
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• 2012

This study aimed at investigating whether a porcine follicular fluid (pFF) supplementation positively affects the characteristics of donor cells and the developmental competence of porcine cloned embryos. Ear fibroblast cells (donor cell) from an Massachusetts General Hospital miniature pig were cultured in different culture methods: (1) Dulbecco's modified Eagle's medium (DMEM)+10% FBS (Control); (2) DMEM+0.5% FBS (SS); and (3) DMEM+10% FBS+10% pFF (pFF) for 72 h. In each conditioned medium, the concentrations of 4 amino acids (Thr, Glu, Pro, and Val) in the pFF group were significantly different from those in the control group (p<0.05 or p<0.01). The proliferation of the cells cultured in the SS group was significantly lower than that of the other treatment groups (p<0.01). The population of apoptotic and necrotic cells in the SS group was significantly higher than that of either the control or the pFF group (p<0.01). The number of embryos that cleaved (p<0.05) and developed into blastocysts (p<0.01) in the SS group was significantly lower than that of either the control or the pFF group. Compared to other groups, the blastocysts produced from the donor cells in the pFF group had higher total cells and lower apoptotic cells (p<0.05). It can be concluded that pFF supplementation in the donor cell culture medium positively affects cell death, cell cycle and quality of the cloned blastocyst.

• Reproductive and Developmental Biology
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• 제32권1호
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• pp.51-58
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• 2008

본 연구는 체세포 복제 한우 송아지의 생산에서 생시체중과 생존성과의 관계에 대하여 살펴보고자 실시하였다. 293두의 한우 대리모에 580개의 복제란을 이식하였다. 복제란의 임신율은 이식 후 50일까지 72.3%로 높았으나, 이후 급격하게 감소하였다. 평균 임신 기간은 복제 송아지에서 287일($279{\sim}295$일)이었으며, 인공수정 송아지도 287일($255{\sim}293$일)로 각각 나타났다. 복제 송아지의 생시체중(30.3kg)은 인공수정 송아지(23.7kg)에 비하여 유의하게 높은 것으로 나타났다(p<0.05). 자연분만(n=17, 29.9kg)과 제왕절개(n=14, 32.3kg)로 태어난 복제 송아지의 생시체중은 차이가 없었다. 하지만, 생후 175일 이전에 사망한 복제 송아지(n=18, 32.8kg)의 생시체중이 175일 이상 생존한 복제 송아지(n=11, 28.3kg)보다 유의적으로 높게 나타났다(p<0.05). 흥미로운 점은 생시체중이 15kg 이하(n=5) 또는 35kg 이상(n=9)인 복제 송아지들은 모두 생후 175일 이전에 폐사하였다. 생후 175일 이전에 폐사한 복제 송아지들(n=20)의 사망 원인은 미성숙 개체 2두(10.0%), 폐와 간 이상 2두(10.0%), 폐의 원인 4두(20.0%), 기형 4두(20.0%), 출생 후 급사(sudden death syndrome) 4두(20.0%) 및 기타 원인불명이 4두(20.0%) 등으로 분류되었다. 이상의 결과를 종합하여보면, 복제 송아지의 정상 생시체중이 6개월 이상을 생존하는데 가장 중요한 요소들 중의 한 가지임을 확인하였다.

• Asian-Australasian Journal of Animal Sciences
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• 제17권10호
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• pp.1369-1373
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• 2004

The percentages of sperm motility and normal acrosome on the liquid boar semen diluted and preserved at $4^{\circ}C$ with lactose hydrate, egg yolk and N-acetyl-D-glucosamine (LEN) diluent were significant differences according to preservation day and incubation time, respectively. The sperm motility steadily declined from 96.9% at 0.5 h incubation to 78.8% at 6 h incubation at 1 day of preservation. However, the sperm motility rapidly declined after 4 day of preservation during incubation. The normal acrosome steadily declined from 93.3% at 0.5 h incubation to 73.8% at 6 h incubation at 1 day of preservation. However, the normal acrosome rapidly declined after 3 day of preservation during incubation. The rates of sperm penetration and polyspermy were higher in 5 and $10{\times}10^6$ sperm/ml than in 0.2 and $1{\times}10^6$ sperm/ml. Mean numbers of sperm in penetrated oocyte were highest in $10{\times}10^6$ sperm/ml compared with other sperm concentrations. The rates of blastocysts from the cleaved oocytes (2-4 cell stage) were highest in $1{\times}10^6$sperm/ml compared with other sperm concentrations. In conclusion, we found out that liquid boar sperm stored at $4^{\circ}C$ could be used for in vitro fertilization of pig oocytes matured in vitro. Also, we recommend $1{\times}10^6$sperm/ml concentration for in vitro fertilization of pig oocytes.