Effect of holding of semen and washing of seminal plasma on quality and fertility of Hampshire boar semen preserved at liquid state

The present study was aimed to reveal the effect on keeping quality of boar semen on holding or not holding at an elevated temperature than that used for preservation when combined with washing or not washing of seminal plasma. Twenty ejaculates, four from each of five Hampshire boars were used to hold for 0 and 4 h in GEPS extender at 22 °C and subsequently washed (1500 × g for 10 min) of seminal plasma or left unwashed and preserved at 15 °C for 72 h after extending with the same extender. The seminal parameters in terms of sperm motility, live spermatozoa, and live spermatozoa with intact acrosome (LIA) were evaluated at 0 h-(immediately after extension) and thereafter at 24 h intervals. The mean percentage of sperm motility was significantly (P < 0.01) higher in unwashed than washed semen at both 0 h and 4 h of holding irrespective of preservation period. It was significantly (P < 0.01) higher in semen held for 4 h than 0 h irrespective of washing and significantly (P < 0.01) lower in washed than in unwashed semen irrespective of holding during preservation. Irrespective of preservation period the mean percentage of live spermatozoa was significantly (P < 0.01) higher with 4 h than 0 h of holding in both unwashed and washed semen and was significantly (P < 0.01) higher in unwashed than washed semen at both 0 h and 4 h of holding. It was significantly (P < 0.01) higher for 4 h held semen irrespective of washing and was significantly (P < 0.01) lower in washed than in unwashed semen irrespective of holding during preservation. The mean percentage of LIA was significantly (P < 0.01) higher with 4 h than with 0 h holding in both unwashed and washed semen and was significantly (P < 0.01) higher in unwashed than in washed semen at both 0 h and 4 h of holding irrespective of preservation period. It was significantly (P < 0.01) higher for 4 h held as compared to unheld semen irrespective of washing and was significantly (P < 0.01) lower in washed than unwashed semen irrespective of holding during preservation. The mean percentage of sperm motility, live spermatozoa and LIA decreased significantly (P < 0.01) in 0 h and 4 h holding irrespective of washing and in unwashed and washed semen irrespective of holding with increase in preservation period. Among all the treatments unwashed semen held for 4 h yielded superior sperm quality on preservation. A total of 32 female pigs were inseminated using preserved semen obtained with the best processing technique found in the study. The conception rate, farrowing rate and litter size at birth were recorded to be 81.25%, 78.13% and 7.96 respectively as compared to 73.38%, 67.57% and 6.68 respectively in the control group. It could be concluded that unwashed Hampshire boar semen held for 4 h, extended with GEPS and preserved at 15 °C for 72 h was conducive to obtain optimum fertility and fecundity in females when used for artificial insemination.