Cryopreservation is mainly used for preservation of boar sperm. However, this method stresses the sperm by reactive oxygen species (ROS), and the conception rate and the litter size are not more efficient than the liquid preservation of spermatozoa. Therefore, we use chitosan which is a natural product derived antioxidant compound. We used GnHA (chitosan+hyaluronic acid) and GnHG (chitosan hydrogel) as chitosan complexes to cryopreserve boar sperm for improve sperm metabolism and function. Sperm parameter (sperm motility, progressive motility, path velocity, straight-line velocity, curvilinear velocity) is measured by computer-assisted sperm analysis (CASA) using frozen sperm with GnHA or GnHG (0, 0.25, 0.5, 1 mg/mL), respectively. Also, lipid peroxidation analysis using malondialdehyde (MDA) is performed to confirm the antioxidative effect of chitosan in frozen spermatozoa. CASA analysis showed GnHA and GnHG are effective against cryopreserved boar sperm. And antioxidant effect is measured by lipid peroxidation analysis. GnHA and GnHG, which is chitosan complex are effective for boar sperm cryopreservation by antioxidant effect.

Cryopreservation is mainly used for preservation of boar sperm. However, this method stresses the sperm by reactive oxygen species (ROS), and the conception rate and the litter size are not more efficient than the liquid preservation of spermatozoa. Therefore, we use chitosan which is a natural product derived antioxidant compound. We used GnHA and GnHG as chitosan complexes to cryopreserve boar sperm for improve sperm metabolism and function. Sperm parameter (sperm motility, progressive motility, path velocity, straight-line velocity, curvilinear velocity) is measured by computer-assisted sperm analysis (CASA) using frozen sperm with GnHA or GnHG (0, 0.25, 0.5, 1 mg/mL). Also, lipid peroxidation analysis using malondialdehyde (MDA) is performed to confirm the antioxidative effect of chitosan in frozen spermatozoa. Sperm motility was higher in GnHA 0.25 mg/mL and GnHG 0.5 mg/mL compared to control. In addition, GnHG 0.5 mg/mL was significantly decreased in lipid peroxidation analysis. The results suggest that GnHA and GnHG are effective for boar sperm cryopreservation by antioxidant effect.

The cryopreservation of sperm has become the subject of research for successful artificial insemination technologies. Antifreeze proteins (AFPs), one of the factors necessary for effective cryopreservation, are derived from certain Antarctic organisms. These proteins decrease the freezing point of water within these organisms to below the temperature of the surrounding seawater to protect the organism from cold shock. Accordingly, a recent study found that AFPs can increase the motility and viability of spermatozoa during cryopreservation.To evaluate this relationship, we performed cryopreservation of boar sperm with AFPs produced in the Arctic yeast Leucosporidium sp. AFP expression system at four concentrations (0, 0.01, 0.1, and 1 μg/ml) and evaluated motility using computer assisted sperm analysis. DNA damage to boar spermatozoa was measured by the comet assay, and sperm membrane integrity and acrosome integrity were evaluated by flow cytometry. The results showed that motility was positively affected by the addition of AFP at each concentration except 1 μg/ml (p<0.001).Although cryopreservation with AFP decreased the viability of the boar sperm using, the tail DNA analyses showed that there was no significant difference between the control and the addition of 0.1 or 0.01 μg/ml AFP. In addition, the percentage of live sperm with intact acrosomes showed the least significant difference between the control and 0.1 μg/ml AFP (p<0.05), but increased with 1 μg/ml AFP (p<0.001). Our results indicate that the addition of AFP during boar sperm cryopreservation can improve viability and acrosome integrity after thawing.

Our objective was to evaluate the function of treahlose and erythritol in reducing ROS concentrations, which is associated with a general improvement in the quality of frozen-thawing miniature pig sperm. Semen was mixed in modified Modena B extender, added to cooling media and freezing media, followed by the supplement of 100 mM trehalose and/or 100 mM erythritol with spermatozoa (1000x 109cells/straw). The trehalose plus erythritol (TE) added group had less intracellular H2O2 than did control and trehalose (36.6±1.6 vs. 49.0±5.8 and 48.8±7.9; P<0.05). The percentage of viable acrosome-intact sperm (FITC-PNA-/PI-) was higher in erythritol and TE than controls (57.0±5.5% and 62.5±4.3% vs. 45.4±5.4%; P<0.05 and P<0.001). The percentage of sperm with high fragmented DNA was observed in control group when compared with erythritol and TE also trehalose (65.5±1.3% vs 59.3±0.7% and 59.0±0.3% vs 62.2± 0.8%; P<0.001). The percentage of sperm LPO was higher in control and trehalose than erythritol (4.4±0.5% and 5.0±0.5% vs. 3.5±0.2; P<0.01 and P<0.001), and was lowest in the TE (control and trehalose vs. TE: P<0.001, erythritol vs. TE: P<0.05). Also, we performed that surgical insemination based on above data to evaluate the function of new cryoprotectant such as trehalose plus erythritol in vivo. Finally, 1 pregnant gilt showed natural estrus was allowed to go to term and 8 live piglets were born. In conclusion, miniature pig sperm was successfully cryopreserved with trehalose plus erythritol provided the increasing the sperm quality and reducing the ROS.

Cryopreservation of miniature pig sperm is essential because of high demand of organ transplant in mass production. However, miniature pig sperm are vulnerable to oxidative stress more than other mammals. Erythritol is a naturally occurring sugar alcohol with powerful antioxidant property. Thus, the aim of our study is to verify if erythritol could reduce lipid peroxide and enhance viability of frozen thawed miniature pig sperm. Ejaculated semen samples were frozen with cryoprotectant subjected to erythritol treatment (0, 10, 100, 500 mM). After frozen thawed, spematozoa viability were examined using the computer assisted sperm analysis (CASA) system. The product of lipid peroxidation, malondialdehyde (MDA) were quantified using spectrophotometer with DPPH and ABTS assays as ROS scavenger markers. Our result showed that erythritol enhanced sperm viability (p<0.05), reduced lipid peroxides significantly (p<0.05), proving the concentration of 100 mM erythritol to be an effective for lowing oxidative damage. Data from our study suggest that erythritol exhibits significant lipid peroxidation scavenging characteristics which may prevent oxidative damage, enhance viability of frozen thawed sperm and thus could be a effective additive as cryoprotectant.

동물의 장기를 인간에게 이식하게 되면 초급성거부반응(Hyperacute rejection, HAR)이 일어난다. 초급성거부반응은 면역계의 구성요소 중 보체(complement)에 의해 일어나는 거부반응으로 돼지의 혈관세포 표면에 있는 Galα(1,3)Gal 당분자에 인간의 항체가 즉각 반응하기 때문에 일어나며, α1,3-galactosyltransferase(α1,3-GT) 유전자는 돼지 혈관세포 표면의 Galα(1,3)Gal 당분자 생성에 관여한다. 따라서 인간에게 돼지의 장기를 이식하기 위해서는 α1,3-galactosyltransferase 유전자를 제거하는 것이 필요한 것으로 알려져 있다. 본 연구실의 이전 연구에서, 시카고 미니돼지 귀체세포에서 상동 재조합(Homologous recombination)을 통해 α1,3-galactosyltransferase 유전자가 제거된 체세포를 개발한 바 있으며, 이 체세포를 통하여 α1,3-GT 유전자가 제거된 돼지도 생산된 바 있다. 본 연구에서는, human serum 처리 시 돼지 세포를 보호해 준다고 보고되고 있는 human complement regulator인 human Decay-accelerating factor(hDAF)와 human α1,2-fucosyltransferase(hHT)유전자를 α1,3-GT 유전자 위치에 gene targeting하여 동시에 hDAF와 hHT가 발현하는 체세포를 개발하였다. Knock-in vector는 hDAF와 hHT 두 유전자가 발현할 수 있도록 IRES로 연결하였으며, α1,3-GT 유전자의 start codon을 이용하여 발현할 수 있도록 구축하였다. 구축한 vector는 electroporation을 통해 미니돼지 체세포에 도입하였으며, PCR 결과, α1,3-GT 유전자 위치에서 상동 재조합이 일어났음을 확인하였다. Positivenegative 선별 방법을 통해 얻은 gene targeting 된 체세포는 RT-PCR에 의해 hDAF와 hHT 유전자의 발현이 확인되었으며, 대조군(NIH minipig)에 비해 α1,3-GT 유전자의 발현이 감소하였다. 또한 이들 세포에 100% human complement serum을 처리하였을 때 knock-in 세포가 대조군에 비해 30% 정도 더 높은 생존율을 보였다. 따라서 개발된 체세포는 이종간 장기이식을 위한 돼지 생산과 함께 이를 이용한 이종간의 장기 이식 시 초급성 거부반응을 억제하는 데 사용될 수 있을 것으로 생각된다.

The main purpose of this study is to estimate the effect of adding Tea-N-Tris (TES) to the freezing buffer for miniature pig sperm. In particular, we attempted to identify the association between the MMPs expression and the fertility and viability of frozen sperm from each extender (LEY (Lactose Egg-Yolk), TLE (TES + LEY), TFGE (TES + Fructose + Glucose Egg-Yolk)). In accordance with this, Hypoosmotic Swelling Test (HOST) respond test was the lowest among sperms frozen in LEY while the highest HOST respond was observed among sperms frozen in TLE. Furthermore, we observed MMPs expression in all sperm groups, with pro-MMP showing lower expression than active MMPs. The expression of MMP-9 and MMP-2 was the highest in sperms frozen in LEY, Meanwhile, sperms from the TFGE and TLE group showed lower level of MMP-9 and MMP-2 expression in the order of TLE being the lowest. LEY group showed lower rate of blastocyst development than the TES supplement group, although the difference was not statistically significant. Meanwhile the rate of blastocyst development appeared similar when sperms from TLE and TFGE group were used for IVF. Together, these results indicate that adding Tea-N-Tris to the sperm freezing buffer only suppresses MMPs protein activation but also maximize in-vitro fertility, providing a means to improve the success rate in the in vitro manipulation of miniature pig sperm.

Cryopreservation and in vitro fertilization (IVF) protocols are important in genetic studies and applications to transgenic animals. Various studies about boar sperm cryopreservation have been studied for a long time. Those were about the use of extenders, the choice of sugars, the cooling and warming rates. The factors that influence the boar sperm are the dramatic changes in temperatures, osmotic and toxic stresses, and reactive oxygen species (ROS) generation. Among these factors, ROS generation is the main damage to DNA which is a principal genetic material and the most important for the practical applications. So we wondered whether ROS generation could be reduced. In previous study, monothioglycerol (MTG) was essential for the culture of embryo stem cells. Therefore we added MTG in the freezing extender based on lactose-egg yolk (LEY) with trehalose. For the assessment of the frozen-thawed sperm, we focused onmotility, membrane integrity and DNA damage. First, we used a computer-aided sperm analysis system for overall conditions of sperm such as motility and viability. Then we performed the sperm chromatin structure assay for DNA integrity and hypo-osmotic swelling test for membrane integrity. And our result showed the existence of MTG in the freezing extender caused less damage to DNA and higher motility in frozen-thawed boar sperm. Also we checked a relative antioxidant activity of MTG in modified Modena B extender. We concluded that this reagent can activate sperm mitochondria at MTG 0.2 μM, contribute to sperm motility and DNA integrity but there was no significant difference on membrane integrity. Also antioxidant activity of MTG in modified Modena B extender was proved.

In this study, we used flow a cytometric assay to evaluate plasma membrane integrity and mitochondrial activity in post-thawed sperm that was supplemented with ginsenoside-Rg1. Varying concentrations of ginsenoside-Rg1 (0, 25, 50 and 100 μM/ml) were used in the extender during cryopreservation to protect the DNA of thawed sperm, thereby increasing the viability and motility rate as evaluated using a computer-assisted sperm analysis (CASA) method. The results derived from CASA were used to compare the fresh, control, and ginsenoside-Rg1 groups. Sperm motility and the number of progressively motile sperm were significantly (p<0.05) higher in the 50 μM/ml ginsenoside-Rg1 group (61.0±4.65%) than in the control (46.6±7.02%), 25 μM/ml (46.2±4.76%), and 100 μM/ml ginsenoside-Rg1 (52.0± 1.90%) groups. However, the velocity distribution of post-thawed sperm did not differ significantly. Membrane integrity and MMP staining as revealed using flow cytometry were significantly (p<0.05) higher (91.6±0.82%) in the 50 μM/ml ginsenoside-Rg1 group than in the other groups. Here, we report that ginsenoside-Rg1 affects the motility and viability of boar spermatozoa. Moreover, ginsenoside- Rg1 can be used as a protective additive for the suppression of intracellular mitochondrial oxidative stress caused by cryopreservation.

The shortage of human organs for transplantation has induced the research on the possibility of using animal as porcine. However, pig to human transplantation as known as xeno-transplantation has major problem as immunorejection. Recently, the solutions of pig to human xenotransplantation are commonly mentioned as having a genetically modification which include alpha 1, 3 galatosyl transferase knockout (GTKO) and immune-suppressing gene transgenic model. Unfortunately, the expression level of transgenic gene is very low activity. Therefore, development of gene overexpression system is the most urgent issue. Also, the tissue specific overexpression system is very important. Because most blood vessels are endothelial cells, establishment of the endothelial-specific promoter is attractive candidates for the introduction of suppressing immunorejection. In this study, we focus the ICAM2 promoter which has endothelial-specific regulatory region. To detect the regulatory region of ICAM2 promoter, we cloned 3.7 kb size mini-pig ICAM2 promoter. We conduct serial deletion of 5' flanking region of mini-pig ICAM2 promoter then selected promoter size as 1 kb, 1.5 kb, 2 kb, 2.5 kb, and 3 kb. To analyze promoter activity, luciferase assay system was conducted among these vectors and compare endothelial activity with epithelial cells. The reporter gene assay revealed that ICAM2 promoter has critical activity in endothelial cells (CPAE) and 1 kb size of ICAM2 promoter activity was significantly increased. Taken together, our studies suggest that mini-pig ICMA2 promoter is endothelial cell specific overexpression promoter and among above all size of promoters, 1 kb size promoter is optimal candidate to overcome the vascular immunorejection in pig to human xenotransplantation.

Miniature pig sperm cryopreservation is continually researched in biotechnology for breed conservation and reproduction. It is important to control the temperature at each stage of cryopreservation and cryoprotectant. It is also necessary to find the optimal cryoprotectant concentration and chemical elements of the extender. Recently, many studies have used various cryoprotectant materials, such as dimethyl sulphoxide (DMSO), ethylene glycol (EG), antifreeze protein (AFP), amides, and glycerol. Glycerol is a commonly used cryoprotectant. However, glycerol has critical cytotoxic properties, including osmotic pressure and it can cause irreversible damage to live cells. Therefore, We focused on membrane fluidity modifications can reduce cell damage from freezing and thawing procedures and evaluated on the positive effects of trehalose to the viability, chromatin integrity, and motility of boar sperm. Miniature pig sperm was separated from semen by washing with modified- Modena B (mMB) extender. After centrifugation, the pellet was diluted with the prepared first extender. This experiment was designed to compare the effects that sperm cryopreservation using two different extenders has on sperm chromatin. The control group used the glycerol only and it was compared with the glycerol and glycerol plus trehalose extender. Sperm viability and motility were evaluated using WST1 assays and computer-assisted semen assays (CASA). Chromatin structure was examined using acridine orange staining. For the motility descriptors, trehalose caused a significant (p<0.01) increase in total motility ( in glycerol vs. in glycerol + trehalose) and progressive ( in glycerol vs. in glycerol + trehalose). A significant (p<0.05) increase in VAP ( vs. ), VSL ( vs. ), VCL ( vs. ), STR ( vs. ), and LIN ( vs. ) were also detected, respectively. The sperm DNA fragmentation index was 48.8% to glycerol only and 30.6% to glycerol plus trehalose. Trehalose added group showed higher percentages of sperm motility, stability of chromatin structure than glycerol only. In this study, we suggest that trehalose is effective in reducing freezing damage to miniature pig sperm and can reduce chromatin damage during cryopreservation.

Hyperacture rejection (HAR) of pig organs, upon xenotransplantation into primates, could partly be overcome by knocking out the alpha-Gal gene. However, xenotransplanted organs may still undergo immunological acture rejection (AR) or acute vascular rejection (AVR). Among several genes involved in AR and AVR, the hCD47 evades the monocyte/ macrophage mediated phagocytosis by identifying the self/non-self signal (CD47-SIRPa) whereas hTFPI participates in the regulation of coagulation pathway by acting upstream of the thrombin. In this study, we investigated hCD47 and hTFPI as two possible candidates for avoiding AR and AVR, respectively upon pig-to-human xenotransplantation. A co-expression vector for hCD47 and hTFPI was constructed using 2A peptides system (F2A) and transfected into the porcine kidney cell line (PK-15). The transfected cells stably expressed both hCD47 and hTFPI mRNA and proteins. Co-culture of non-transfected, hCD47-transfected, hTFPI-transfected or hCD47+hTPFI-transfected PK15 cells with natural killer (NK) cells, monocytes and macrophages confirmed the cytotoxic effect of hCD47 and revealed a synergistic effect of hCD47 and hTFPI co-transfection. There was an attractive survivability of 25～30% on each type of innate immune cell, NK cell and macrophage. These results suggest that transgenic pigs, genetically modified for hCD47 and hTFPI may be useful for overcoming xenograft rejection. Furthermore, cotransfection with hTFPI may enhance the cytotoxic effect of hCD47, possibly by assisting the hCD47-SIRPa binding by an unknown mechanism.

The main purpose of this study is to estimate the effect of adding Tea-N-Tris to the freezing buffer for miniaturepig sperm. In particular, we attempted to identify the association between the MMPs expression and the survival and viability of sperms. Prior to freezing, sperms in LEY without Tea-N-Tris showed 40.3±2.8% viability and 60.3±1.3% acrosome intact rate at 4℃. After freezing, sperms stored in LEY (lactose+Egg yolk) with Tea-N-Tris (=TLE) showed the highest viability (57.4±1.8%) and acrosome intact rate (65.6±4.6%). In accordance with this, DNA fragmentation was the highest among sperms frozen in LEY while the lowest fragmentation was observed among sperms frozen in TLE. When these sperms were used for in vitro fertilization (IVF), the LEY group showed lower rate of blastocyst development, although the difference was not statistically significant. Meanwhile the rate of blastocyst development appeared similar when sperms from TLE and TFGE (Tea-N-Tris+Fructose+ Glucose+Egg yolk) group were used for IVF. We observed MMPs expression in all sperm groups, with pro-MMP showing lower expression than active MMPs. The expression of MMP-9 and MMP-2 was the highest in sperms frozen in LEY, Meanwhile, sperms from the TFGE and TLE group showed lower level of MMP-9 and MMP-2 expression in the order of TLE being the lowest. Together, these results indicate that adding Tea-N-Tris to the sperm freezing buffer would not only suppress MMPs expression but also minimize DNA fragmentation, providing a mean to improve the success rate in the in vitro manipulation of miniaturepig sperms. * This work was supported by BioGreen 21 Program (No. PJ008029). Rural Development Administation, Republic of Korea.

The objective of this study is to estimate the effect of adding TES to LEY and FGE freezing extender for the sperm viability, acrosomal morphology and DNA fragmentation from miniature pig sperm, we evaluated sperm characteristics in TFGE, TLE and LEY with various thawing condition ( for 20 sec, 45 sec and for 5 sec, respectively), and in different concentration of glycerol at 1%, 1.5%, 3%. The sperm viability and normal acrosome intact(NAI) in TFGE (Viability : , NAI : ), TLE (, ) extender significantly(p<0.05) increased than that in LEY (, ) extender thawed at for 5 sec. According to the results from glycerol concentration, the viability and NAI of miniature pig sperm in 1.5% glycerol TLE (, ) was highest among the experimental groups. In accordance with this, DNA fragmentation rates was the lowest in TLE () while that in LEY () is the highest. Therefore, these results suggest that TLE extender method for freezing- thawing of miniature pig sperm increased the viability after thawing.

Somatic cell nuclear transfer (SCNT) for miniature pig has been developed for xenotransplantation and many other biomedical experiments. However, the efficiency of SCNT is still very low due to many factors. To optimize the surrogate mother condition for improvement of cloned miniature pigs efficiency, we investigated the effect of the status of surrogate mother on pregnancy, farrowed rate in SCNT pigs. After SCNT with mesenchymal stem cells as donor cells, the SCNT embryos were surgically transferred into the oviduct of surrogated pigs. To compare the effects of status of surrogate pigs on pregnancy, surrogate pigs were prepared by artificial abortion at day 20~29 (Group 1), 30~39 (Group 2), and 40~45 (Group 3) of gestation. After SCNT embryos transfer in three different status of surrogate pigs, Group 2 (56.3%) and 3 (55.6%) had significantly ( <0.05) higher the pregnancy rate than group 1 (0%) at day 30 of gestation. The status of ovulation in surrogate pig also was investigated. Post-ovulation status (54.8%) had higher proportion than pre-ovulation status (38.7%) and ovulation status (6.5%). We obtained 19 cloned miniature piglets from seven surrogate gilts and five piglets are living healthy but fourteen piglets died soon after birth or stillbirth. The weights of piglets greatly differ from 254 to 1,296 g. Microsatellite analysis showed that cloned piglets were genetically different from the surrogate mother and cloned piglets were genetically equal to the donor cell. In conclusion, the present result indicates that artificially abortion method can improve the efficiency of pregnancy after SCNT in pigs. This study will provide available method for the further study and application in the field of xenotransplantation.

The objective of this study was to evaluate the effect of Tea-N-tris medium on the sperm viability and acrosomal morphology for semen of normal and miniaure pig by type of freezing extender. The present study was to determine of Tea-N-tris (0.02 g/ml) effect to freezing extender LEY(Lactose 11% + Egg yolk 20%) and FGE(Fructose 3%+Glucose 7%+Egg yolk 20%) for the spermatozoa viability, acrosomal morphology and DNA fragmented analysis from normal and miniature pig semen, were evaluated freezing extender TFGE, TLE and LEY during thawing at 37℃ for 45 sec and 75℃ for 5 sec, respectively. Interestingly, the result that sperm after addition of Tea-N-tris extender(TFGE, TLE) during 15 4℃ cooling significantly increased the viability(p<0.05), as compared to than of sperm cooling in LEY extender, but lower the percentage of AR(acrosome reacted spermatozoa) pattern than LEY extender. The sperm viability and AR pattern after freezing was appeared like sperm cooling method pattern. And treatment spermatozoa during freezing after addition of Tea-N-tris extender significantly (p<0.05) increased the viability and AR to miniature pig sperm, than normal pig sperm, but most highly percentage of viability and AR pattern to normal pig sperm during freezing in LEY extender. Chromosomal DNA fragmentation increased from LEY extender to sperm of normal and miniature pig, but decreased from the Tea-N-tris extender. Therefore, suggest that Tea-N-tris freezing extender method for freezing of miniature pig sperm is required for increasing viability. This Study was supported by Technology Development Program for Agriculture and Forestry, Ministry for Food, Agriculture, Forestry and Fisheries, Republic of Korea.

The purpose of this study was undertaken to evaluate of cryopreservation efficiency in α 1,3-galactosyltransferase knock-out(GalT KO) cloned miniature pig sperm. To compare ability of frozen-thawed sperm characteristics, three different pig strains (GalT KO) cloned miniature pig, PWG miniature pig and Duroc were used. The ejaculated semen from the three pig species was diluted with same volume extender and added to LEY solution for freezing. The diluted semen was placed in 0.5 ml straws, and freezing was initiated by exposing the straws to liquid nitrogen (LN2) vapours for 10 min before placing them into LN2 for cryopreservation. A fter thawing, the sperm ability were assessed for viability (SYBR-14/PI staining), abnormality (Rose Bengal staining), and acrosome status (intactness, intensity and capacitation) (chlorotetracycline, CTC staining). The viability of frozen-thawed GalT KO pig sperm had no significant difference as compared with Duroc and PWG miniature pig sperm. However, The CTC pattern of frozen-thawed GalT KO cloned miniature pig spermatozoa showed significantly lower rates in F pattern and AR pattern (p<0.05) and significantly higher rates in B pattern than Duroc and PWG miniature pig (p<0.05). The abnormality of GalT KO cloned miniature pig sperm was significantly lower as compared to Duroc and PWG miniature pig sperm (p<0.05). In conclusion, GalT KO cloned miniature pig semen can be cryopreserved successfully and used for artificial insemination reasonably.

This study was conducted to establish a freezing method of miniature pig spermatozoa. The semen ejaculated from PWG M-type miniature pig was collected by gloved-hand method. The semen was diluted with same volume extender (m-Modena B). The frozen solution used frozen solution of four different (LEY, TCG, BF-5 and m-Modena+egg yolk) for find optimal frozen solution in miniature pig sperm. The diluted semen for frozen rate assay was added to LEY solution (solution Ⅰ: 11% lactose+egg yolk; solution Ⅱ: solutionⅠ+glycerol+OEP), and frozen depending on freezing rate by the three different freezing methods (A: until 5℃ for 1 hrs, holding at —102℃ for 10 min; B: until 5℃ for 2 hrs, holding at —102℃ for 10 min; C: until 5℃ for 3 hrs, holding at —80 and —102℃ for 10 min). Semen cooled until 5℃ was added with glycerol 1, 3 and 5%, and take a equilibrium time for 0, 10 and 30min. Frozen-thawed sperm were evaluated for viability, acrosomal status and morphological abnormality. The results of frozen-thawed sperm ability by frozen solution, viability was higher in LEY solution compared to other three different frozen solution. AR pattern of LEY solution were lower than other three different frozen solution. The results of freezing rate, viability was higher in B method compared to other methods (p<0.05). Acrosomal statute was intacted in A and B methods than C method. The experiment for glycerol condition was showed that sperm viability was higher in extender with 1% and 3% glycerol and equilibrium time of 0 min. The acrosome damage was lower in extender with 1% glycerol and equilibrium time of 10 min than other conditions. In conclusion, the optimal conditions for cryopreservation of miniature pig spermatozoa obtained in LEY frozen solution, cooling rate of 1～2 hrs, 1～3% glycerol concentrations and glycerol equilibrium time of 0～10 min.

This study was undertaken to find out the effect of methyl-beta-cyclodextrin (MBCD) on cold shock and membrane cholesterol quantity of sperm during the freezing process in miniature pigs. For this study, semen ejaculated from PWG M-type miniature pig was diluted that freezing solution (with egg yolk group) and m-Modena B (without egg yolk group) treated with 0, 1, 5, 10 and 20 mM MBCD before freezing process. The diluted semen was monitored sperm ability at room temperature, after cooled until 5℃ and after forzen-thawed for cold shock test of spermatozoa. Also, membrane cholesterol of sperm was extracted by folch solution at the same time. sperm ability was assessed for viability and acrosomal status. The membrane cholesterol quantity was measured by thin-layer chromatography (TLC) method. The result, viability and acrosome integrity in semen diluted without egg yolk groups were decreased at all temperature range by increasing of MBCD concentration. In particular, sperm of egg yolk group was showed that significantly higher viability and lower acrosome damage when treated with 5 mM MBCD (p<0.05). The results of TLC experiment, cholesterol amounts were increased with MBCD cocentration in egg yolk, and decreased with MBCD concentration in m-Modena B. In cryopreservation efficiency, there was no significant difference at viability, and acrosomal state of sperm in 5 mM MBCD concentration was significantly lower in acrosome damage than other groups (p<0.05). Therefore, the addition MBCD in egg yolk was protected spermatozoa from cold shock injury. This protective effect of MBCD may be due to addition of sperm membrane cholesterol.