Liquid Boar Sperm Quality during Storage and In vitro Fertilization and Culture of Pig Oocytes

The percentages of sperm motility and normal acrosome on the liquid boar semen diluted and preserved at $4^{\circ}C$ with lactose hydrate, egg yolk and N-acetyl-D-glucosamine (LEN) diluent were significant differences according to preservation day and incubation time, respectively. The sperm motility steadily declined from 96.9% at 0.5 h incubation to 78.8% at 6 h incubation at 1 day of preservation. However, the sperm motility rapidly declined after 4 day of preservation during incubation. The normal acrosome steadily declined from 93.3% at 0.5 h incubation to 73.8% at 6 h incubation at 1 day of preservation. However, the normal acrosome rapidly declined after 3 day of preservation during incubation. The rates of sperm penetration and polyspermy were higher in 5 and $10{\times}10^6$ sperm/ml than in 0.2 and $1{\times}10^6$ sperm/ml. Mean numbers of sperm in penetrated oocyte were highest in $10{\times}10^6$ sperm/ml compared with other sperm concentrations. The rates of blastocysts from the cleaved oocytes (2-4 cell stage) were highest in $1{\times}10^6$sperm/ml compared with other sperm concentrations. In conclusion, we found out that liquid boar sperm stored at $4^{\circ}C$ could be used for in vitro fertilization of pig oocytes matured in vitro. Also, we recommend $1{\times}10^6$sperm/ml concentration for in vitro fertilization of pig oocytes.