The experiment tested different ways to freeze boar sperm. They used different extenders, detergents, and cooling methods. Extender Ⅳ had the lowest sperm motility, but was best for thawing. Adding detergent improved sperm motility, with no difference between SDS and OEP. The cooling method didn't affect sperm motility after thawing. Caffeine helped boost the motility of frozen-thawed sperm.