Effect of the Extender,Detergent and Cooling Prolocols on Freezing Boar Sperm

The experiment in the effects of extender, detergent and cooling protocols on freezing boar semen was carried out. Fresh sperm were diluted by extendersⅠ～Ⅳ and enclosed in 5 ml straw. After placed in liquid nitrogen vapor, frozen sperm was thawed or stored for 3 h. The motility of sperm was detected. The result was following:①the motility in extender Ⅳ was lowest in four groups(at thawing: 60.0 %,57.2 %,56.3 % and 50.6 %,P0.05; at 3 h storage: 17.9 %, 15.1 %, 13.5 % and 9.3 %,P0.05); however, the extender Ⅳ was better than other groups as thawing dilution(at 3 h storage: 4.2 %, 6.8 %, 12.1 %, 32.8 %, P0.05).②when detergent(SDS or OEP) were added to extender, the motility was promoted, but there was no significantly different between SDS and OEP.③ freezing protocols of 2-step cooling-down method(-70 ,-110 ℃) and 1-step cooling method(-110 ℃) had no effect on the percentage of motility after thawing. The addition of caffeine could promote the motility of frozen-thawed sperm.