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.

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.

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.

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.

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.

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 undertaken to find out the effect of cholesterol and serum albumin on sperm ability and lipid peroxidation levels period to the liquid storage of miniature pig sperm. Ejaculated semen from miniature pigs was collected by gloved-hand method into a pre-warmed () thermos bottle, and extended with Modena solution {with and without BSA, methyl-beta-cyclodextrin (-cholesterol) and cholesterol loaded cyclodextrin (+cholesterol)}. Each semen was assessed for viability (SYBR-14/PI staining) and acrosome intactness, intensity and capacitation status by chlorotetracycline (CTC) staining at 1, 3, 5, 7 and 10 days of storage. At for the effects of cholesterol and serum albumin on lipid peroxidation, semen were incubated with (), and lipid peroxidation level were measured by flow cytometry using the lipid peroxidation reporter probe . The result, lipid peroxidation level in sperm added with cholesterol were lower in compared to the added sperm with serum albumin. Also, added cholesterol to sperm had significant (p<0.05) higher viability when storage for 7 and 10 days and lower when 10 days of storage percentage of acrosome-reacted sperm (AR pattern) in acrosome state as say result compared to other treated groups. In conclusion, role of cholesterol during lipid storage in miniature pig spermatozoa was protected boar spermatozoa from lipid peroxidation prior to lipid storage. Addition serum albumin during lipid storage in sperm may be induce sperm membrane damage by lipid peroxidation. Therefore, addition of cholesterol to miniature pig sperm will be lead to extension of liquid storage periods.

The objective of this study was to evaluate the sperm liquid storage diluted with Brine Mineral Water (BMW) in miniature pig. Therefore we performed to find optimal concentration of BMW. The ejaculated semen from miniature pig was collected by gloved-hand method. The collected semen was diluted with dilution solution (Mulberry Ⅲ; modified-Modena B) which BMW was added. Concentration of BMW was 0, 2.5, 5, 7.5, 10 and 12.5% in dilution solution. The diluted semen was preserved at 17℃. Sperm ability was estimated by viability, capacitation acrosome reaction using chlortetracycline (CTC), hypoosmotic swelling test (HOST), morphologic abnormality. The diluted semen was observed for 7 days. The viability was significantly measured higher at 2.5% concentration of BMW than other groups (p<0.05). The AR-pattern of CTC analysis was significantly measured lower at 12.5% concentration of BMW than other groups (p<0.05). However, abnormality was not significantly different among all the groups (p<0.05). In conclusion, viability of sperm was the highest at 2.5% concentration of BMW but BMW had a negative effect on HOST, capacitation and acrosome reaction in sperm of miniature pig.

The objective of this study was to evaluated the efficiency of sperm cryosurvival using each extenders Triladyl and LEY containing egg yolk to the cryopreservation of separated sperm by percoll in miniature pig. The ejaculated semen from miniature pig was separated by 65% percoll and un-separated sperm as a control before freezing. The freezing of diluted semen added with Triladyl containing egg yolk and LEY solution (solution Ⅰ: 11% Lactose or Triladyl + egg yolk; solution Ⅱ: solutionⅠ + glycerol + OEP). Analysis of sperm ability was estimated by viability, capacitation acrosome reaction using chlortetracycline (CTC) the morphologic abnormality and hypoosmotic swelling test(HOST). The groups were designed that as separated sperm by Percoll with Triladyl(ST) or LEY(SL) for cryopreservation. And unseparated sperm with Triladyl(UT) or LEY(UL). As a results, the viability was higher significantly(p<0.05) in ST, SL, UT than UL extender. The morphologic abnormality was measured significantly (p< 0.05) lower in ST than other extenders. The AR-patterned in CTC analysis was measured significantly(p<0.05) lower in SL and UL than other extenders. In conclusion, using Triladyl extender resulted in viability and morphology of separated sperm by percoll that were effective than using LEY extender, but it resulted in capacitation acrosome reaction was lower than using LEY extender.

The objectives of this study was to evaluate the efficiency of the bacteria eliminated sperm by percoll gradient method on sperm quality and embryo cleavage in vitro in pig. The semen of miniature pig collected by gloved-hand method pre-warmed (37℃) in thermos bottle, and separated by 65% percoll. Analysis of sperm ability was estimated by examining viability, capacitation and acrosome reaction using chlortetracycline (CTC) and the abnormality. Also, fertility of sperm was monitored with cleavage rate of embryo after IVF using separated and un-separated sperm by percoll. The result, viability of separated sperm was significantly(p<0.05) higher(83.6±2.0 vs 59.0±4.4%) than un- separated sperm. The results of CTC analysis showed the percentage of F- and B-patterned separated sperm was higher in separated that than un-separated sperm. On the contrary, the percentage of AR-patterned form un-separaed sperm was significantly(p<0.05) higher(13.6±0.8 vs 8.1±0.6%) than separated sperm. Also, abnormality of un-separated sperm was significantly(p<0.05) higher(20.2±0.4 vs 16.8±2.8%) than separated sperm. However, the cleavage rates of embryo using separated sperm by percoll and un-separated sperm had not significantly difference on 2 cell stage(9.25 vs 11.88%), 4 cell stage(26.76 vs 24.51%) and >4 cell stage(63.99 vs 63.61%) at 48h of IVF. Therefore, the sperm separated by percoll method showed improvement in sperm quality than un-separated sperm in miniature pig.

This study was conducted to investigate the effect of periods of sperm preincubation, concentrations and storage periods of miniature pig sperm on in vitro penetration of porcine follicular oocytes. High concentration (1×105, 2.5×105, 5×105, 1×106, 5×106 and 1×107) did support sperm penetration than low concentrations (P<0.05). However, polyspermic oocyte rates were increased with high concentrations of sperm. On the other hand, sperm preincubated during 1, 2 or 5h could be penetrated than sperm preincubated during 0, 3 or 4h (P<0.05). When sperm were storaged with different periods, in vitro pentration rates were significantly higher 0～2 days than 3～4 days of sperm storage (p<0.05). These results indicate that sperm treatment factors can effect in vitro penetration in miniature pig.

본 연구는 0.5 ml straw를 이용한 정자 동결융해 시 융해 온도가 동결정자의 성상에 미치는 영향을 파악하고 미니 돼지의 동결정액에 최적화된 적정 융해 조건을 찾기 위하여 실시하였다. 정액동결 straw를 37, 50 및 70℃에서 각각 5초, 10초 및 45초간 융해하여 생존율(SYBR-14/PI staining), 정자원형질막기능검사 (Hypoosmotic Swelling Test) 및 첨체반응율 (CTC : chlorotetracycline staining)을 검사 한 결과 70℃에서 5초간 융해한 정자의 생존율과 CTC 결과가 37℃와 50℃에서 10초 및 45초간 융해한 처리구보다 유의적(p<0.05)으로 높은 생존율과 낮은 비율의 첨체 반응율을 얻었다. 따라서 미니 돼지의 동결 정액은 고온에서 단시간 융해를 하는 것이 정자의 성상에 유리한 것으로 사료된다.

The purpose of this study was to assess sperm quality during in vitro storage of miniature-pig semen in order to determine which extender should be used and how extender can be diluted for in vitro storage of miniature-pig semen. Freshly ejaculated miniature-pig's semen was diluted with same volumes of Beltsville Thawing Solution (BTS), Androhep, Modena, Mulberry III and modified-Modena extenders. Sperm quality was evaluated by examining viability, motility, abnormality, acrosome intactness, intensity and capacitation status by chlorotetracycline (CTC) staining. Sperm motility decreased with storage period prolonged and differences among BTS, Androhep, Modena and Mulberry III were apparent On Day 1, approximately 80% of the sperm were motile, but motility decreased to 40% at Day 7. During the 7 days of storage, sperm survival in modified-Modena B extender was higher than another extenders. However, it was not differ significantly among other extenders. The percentage of F and B patterns were not differ significantly among the extenders. However, F pattern in modified-Modena B extender was slightly higher until 3 days of storage than that of Modena extender, modified-Modena A extender and modified-Modena C extender. The percentage of AR patterns in modified-Modena B extender was slightly lower, but did not differ significantly among other extenders. The results of present study suggest that modified-Modena B was effective as new extender for in vitro storage of miniature-pig semen.

The purpose of this study was the analysis of sperm ability in Specific Pathogen Free (SPE) miniature pig for production of bio-organ. The collected semen was diluted with extender and stored at 17℃ for up to 7 days. The semen samples were evaluated at 0, 1, 3, 5, and 7 days of storage for analysis of sperm ability. Sperm ability was evaluated by examining viability, progressive motility, sperm abnormality and intensity of the sperm membrane. Also, the semen was processed according to the convenient freezing method, and frozen-thawed sperm was evaluated by examining viability, capacitation and acrosome reaction using chlortetracycline (CTC) staining. Motility of spermatozoa of SPF miniature pig was significantly (P<0.05) lower on 3 days or later compared to the Duroc, Yorkshire and Landrace in domestic boar. The percentage of abnormal spermatozoa of Landrace were significantly (P<0.05) higher than in SPF miniature pig, Duroc and Yorkshire that had a similar percentage on 5 or 7 days of sperm storage. The percentage of spermatozoa with coiled tail decreased during the storage period but there were no significant difference. On the other hand, viability of frozen-thawed spermatozoa had a significantly (P<0.05) lower in SPF miniature pig than in other domestic boars. CTC patterns had no significant difference, but SPF miniature pig had higher percentage of capacitated spermatozoa and lower percentage of acrosome-reacted it than domestic boars. Therefore, this study suggest that it is necessary to develop the suitable extender and freezing methods methods for the high viable rate and fertilizing ability in vitro.