This study was performed to investigate the characteristics within ages and freezing tolerance of spermatozoa in Jindo Dog. Experimental animals were selected 12 herds within 1～8 year’s old and collected semen for 2 times in a week. Collected semen was evaluated whole volume and sperm number with CASA system (SIAS, Medical Supply, Korea). Then seminal plasma were separated and diluted with modified Tris-egg yolk extender and added 4, 6 and 8% glycerol for 4 times to final concentration and equilibrated for 1.5 hrs. Before and after freezing, equilibrated semen were evaluated the survival rates. Total volume of sperm at 1～2 year old group is as 5.2×108 cells/ ml largest and there were no significance among groups. The motility of 1～2 year old group is highest as 90.9% and there were significance among groups. Abnormal sperm showed similar among groups. The survival rate in terms of pre-freezing and post-freezing were decreased all levels of glycerol and reveled 87.0% to 64.5% in 4%, 87.5% to 51.9% in 6% and 73.4% to 29.7% in 8%, there were significant difference among the groups (p<0.05). These results suggest that the optimal sperm-freezing methods in Jindo Dog are utilized with modified Tris egg-yolk extender with 4% glycerol and were improve the reproductive activity by these methods.

This studies were conducted to investigate the survival rate of frozen-thawed spermatozoa of Jindo Dog by monosaccharide and freezing rates. Experimental animals were prepared 12 males within 1~8 year's old and collected once in a couple of weeks by digital manuplation methods. Collected semen was diluted 1:1 with Tris-egg yolk extender and added 4, 6 or 8% of glycerol and none, 4 mM glucose or 4 mM fructose as cryoprotectant and was equilibrated for 2 hrs in . In monosaccharide groups, the freezing rate was 5 cm-5 min. above . The survival rates without monosaccharide were , , in 4, 6 or 8% glycerol, respectively. In addition of glucose, the survival rates were , , in 4, 6 or 8% glycerol, respectively and in fructose, were , , in 4, 6 or 8% glycerol, respectively. There showed significantly different between glycerol groups and monosaccharides groups (p<0.05). The survival rates of freezing rate in 5 cm-5 min. group was , , and in 10 cm-10 min. group was , , in 4, 6 or 8% glycerol, respectively. There were significantly different between freezing rates (p<0.05). These results suggest that the addition of fructose with 6%-glycerol and slow freezing improve the survival of frozen-thawed sperm in Jindo Dog.