The objective of this study was two folds: to investigate the relationship between paternal identification rate and sperm quality parameters such as motility and sperm chromatin structure assay after heterospermic insemination; to see if mutual complement between tests and development of useful technique to enhance the fertility in artificial insemination. In individual boar's fertilizing ability, 3 high fertility boars showed significantly high fertility (p<0.05) compared to 3 low fertility boars, but there was no difference in litter size between two groups. Sperm motility test in pooled and individual semen using computer assisted sperm analysis (CASA) revealed that no significant difference among boars. The high fertile boar showed tendency of low %Red (High red fluorescence/green+red fluorescence) in sperm chromatin structure assay (SCSA) but paternal identification rate from piglets did not differ after heterospermic insemination. The correlation coefficient between individual or pooled semen function test and farrowing rates were well correlated as follows: %Red with litter size (r= - 0.53, p=0.03); %Red with paternal identification rates (r=-0.51, p=0.03); paternal identification rates with litter size (r=0.57, p=0.02). These results indicate that sperm chromatin structure assay and sperm quality parameter test in pooled semen are useful method to predict and evaluate the fertilizing capacity after heterospermic insemination in boars.

The objective of this study was to determine the potential hazardous effects of sorting process by flowcytometry on the quality of boar spermatozoa by flowcytometer. Freshly collected boar semen was diluted and divided into two groups; control none sorted and sorted. Sperms in sorted group were processed with flowcytometer for cell sorting with 100 uM nozzle under the 20 psi pressure. Measurements on each parameter were made at two time points, 0hr (right after sorting) and 24 hr post sorting. Although there was a tendency of lower viability in sorted group than none sorted control group, the percentage of live cells in control(75.83+-6.92 & 59.53+-10.34) was not significantly different from sorted (59.7+-7.34 & 43.97+-3.76) at both 0 and 24 hr post sorting. However, sorted sperm showed significantly lower mitochondrial function compared to the control at both 0 h (79.37+-3.22 vs. 63.50+-10.05) and 24hr(67.27+-3.22 vs. 46.97+-5.37) time points (p<0.007). Sperm DNA fragmentation rate was significantly lower in control (22.0+-7.04) than that of sorted (32.27+-7.49) at 24 hr time point (p<0.0002). Taken together, these data suggested thatsorting process by flowcytometer may have influenced sperm motility rather than viability. Also high speed sperm sorting by flowcytometer has significant effects on DNA fragmentation on elapsed time after sorting.

The objective of this study was to determine the effect of administration of Prostaglandin F2α (PGF2α) on semen collection training and semen characteristics in sexually inexperienced boars. Boars were moved individually to a semen collection pen and were trained to mount dummy sow. During the first and second semen collection secessions, 4 out of 17 boars and 4 out of remaining 13 boars allowed collection of semen. The 9 boars that failed semen collection from first 2 attempts received immediately 15 mg of PGF2α i.m. (intramuscular injection) upon entering the collection pen for semen collection resulted in successful semen collection from all 9 boars. Total numbers of spermatozoa were higher in PGF2α treated boars but there was no significant difference in % motility kinematics characteristics between control and PGF2α treated groups during 72 hr period. Overall, administration of PGF2α in sexually inexperienced boars increased the sex drive and facilitated the mounting activity to the dummy sow for semen collection.