We observed MMPs expression in all sperm groups, with pro-MMP showing lower expression than active MMPs. According to the results from each freezing extender, the sperm membrane integrity (HOST: Hypoosmotic Swelling Test) analysis in TCGGD (Tris 250 mM, Citric acid 88 mM, Glucose 47 mM, Glycerol 3%, Dimethylsulpoxide 3.5 M) is 59.8 ± 0.7, TCGSD (Tris 250 mM, Citric acid 88 mM, Glucose 47 mM, Sucrose 0.1 M, Dimethylsulpoxide 3.5 M) is 59.3 ± 0.5 were significantly higher (p < 0.05) among the experimental groups. And MMPs analysis result, we observed MMPs expression in all sperm groups, with pro-MMP showing lower expression than active MMPs. The expression of active MMP-2 was the highest in sperms frozen in TCGSD and TCGD (Tris 250 mM, Citric acid 88 mM, Glucose 47 mM, Dimethylsulpoxide 3.5 M), Meanwhile, sperms from the TCGGD and TCGED (Tris 250 mM, Citric acid 88 mM, Glucose 47 mM, Ethylene glycol 3%, Dimethylsulpoxide 3.5 M) group showed lower level of active MMP-2 expression. Together, these results indicate that adding glycerol or sucrose 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 rabbit sperms. Therefore, these results suggest that TCGGD or TCGSD extender method for freezing-thawing of rabbit sperm increased the viability after thawing.

Sexed sperm can contribute to increase the profitability of the cow industry through the production of offspring of the craved sex, such as males for meat or females for dairy production. Therefore, the utilization of sexed sperms plays a very important role in the production of offspring of superior cattle. In this study, we examined the pregnancy rates and calves sexing proportion of male and female calves produced using AI, both performed using sexed and conventional sperm. In the result, the conception rates after ET were 73.3% (33/45) sexed semen and 52% (55/104) conventional semen. Thus, the sex ratio for sexed-semen inseminations was 70% (21/30) females for singleton births within a 272 to 292 day gestation interval. The sex ratio for conventional semen was 61% (34/56) females for births. As a result, it is suggested that the use of sex classification sperm will play a very important role in the offspring production of Korean bovine.

The purpose of this study was to evaluate the effect of addition of ethylene glycol, glycerol and sucrose to TCG (Tris, Citric Acid, Glucose, Egg Yolk) and DMSO Frozen. The extender containing Egg yolk concentration (10%, 20%) affects viability and acrosome morphology of rabbit sperm. Sperm viability was then assessed for the freezing extenders TCGD (Tris + Citricacid + Glucose + DMSO), TCGED (Tris + Citricacid + Glucose + Egg yolk + DMSO), TCGGD (Tris + Citricacid + Glucose + Glycerol + DMSO) and TCGSD Tris + Citricacid + Glucose + Sucrose + DMSO) during thawing at 38oC. for 20 seconds, respectively. TCG + 10% egg yolk (viability: 77.0 ± 0.8, NAI: 73.3 ± 0.9) was significantly (sperm viability and normal acrosome interaction (NAI)) higher than TCG + 20% egg yolk (70.7 ± 1.1, 70.0 ± 0.9) in the sperm normalcy analysis according to the yolk concentration. TCGGD (53.4 ± 0.1, 62.3 ± 0.4), TCGSD (61.3 ± 0.0, 67.1 ± 0.1) sperm viability and normal acrosome interaction (NAI) in frozen spermatozoa are TCGD (46.4 ± 2.8 and 56.3 ± 1. 4) and TCGED (23.0 ± 1.1 and 54.6 ± 1.4) extenders was thawed at 38oC for 20 seconds. According to the results from each frozen bulking agent, sperm membrane integrity by hypotonic swelling test (HOST) analysis in TCGGD (59.8 ± 0.7), TCGSD (59.3 ± 0.5) was significantly high compared to other experimental groups (p < 0.05). In conclusion, these results suggested that TCGGD and TCGSD extenders enhance survivability of rabbit sperm after frozen-thawing.

The purpose of this study was to analyze whether FSH and LH hormone treatment directly or indirectly affect embryo development in embryonic development. To determine this, we compared the development of embryonic cells through the expression pattern of MMPs. As a result, 33.8% of blastocysts were formed in FSH added group, 20.8% in LH added group and 10% in FSH + LH added group. In addition, the activity of MMP-9 was highly detected in the FSH-added group, and the expression of Casp-3 was much lower than that of the other groups. These results suggest that the addition of FSH seems to increase the activity of MMP-9 in embryonic cells, and that LH, on the contrary, may activate MMP-2 activity. In addition, the expression level of MMP-2 in the FSH-added group was high in the Trophoblast cell group and in the LH-added group, the hormone ideal secretion might affect the development of the embryonic cell.

Here, we evaluated the mode of programmed cell death during porcine oocyte maturation by comparing the two major pathways associated with programmed cell death, apoptosis (type I), and autophagy (type II). We investigated the expression and localization of major genes involved in autophagy and apoptosis at mRNA and protein levels. Furthermore, the effect of hormonal stimulation on autophagy and apoptosis was analyzed. We found that the activity of autophagy-associated genes was increased in the cumulus-oocyte complexes (COCs) following follicle-stimulating hormone (FSH) treatment, while the addition of luteinizing hormone (LH) reversed this effect. The expression of proteins associated with autophagy was the highest in FSH-treated COCs. On the other hand, caspase-3 protein level was maximum in COCs cultured with LH. The treatment with rapamycin resulted in the effect similar to that observed with FSH treatment and increased autophagy activity. Thus, hormonal stimulation of pig oocytes resulted in distinct patterns of maturation. The high-quality oocytes majorly relied on the type II pathway (autophagy), while the type I pathway (apoptosis) was more prominent among poor-quality oocytes. Further investigation of this distinction may allow the development of techniques to produce high-quality oocytes in porcine in vitro fertilization.

The objective of this study was to investigate the expression of bovine luteum expressed sequence tags (ESTs), vascular endothelial growth factor (VEGF), and tumor necrosis factor receptor 1 (TNFR1) and the presence of functional ESTs in the bovine corpus luteum (CL) during different stages of the estrus cycle. Reverse transcription-polymerase chain reaction (RT-PCR) analysis showed a difference in the expression of ESTs during the CL stage. Concentration of ESTs in the CL tissue increased significantly from the mid-luteal stage and decreased thereafter. RT-PCR analysis showed higher levels of the EST genes in the CL of the mid-luteal stage than in other stages, and the same level of expression of VEGF. Immunohistochemistry analysis of the tissue from CL formation to regression showed low cytosol and aggregation of the nucleus. And activity caspase 3 (apoptosis detector) was most strongly detected in the CL1 stage of bovine. During the estrous cycle, the cytosol was magnified and differentiation of the nucleus was clearly manifested. The ESTs affected the CL, and the relationship between VEGF and TNFR1 played a pivotal role for CL development and activation, dependent on the stage of CL. These results suggest local production of ESTs, the presence of functional ESTs in the bovine CL, and that ESTs play a role in regulating the function of cell death in bovine CL.