Abstract: The objective of this study was designed to determine the effect of soybean lecithin replace of egg yolk in the cryopreservation of stallion semen. After collecting, stallion semen was divided into four aliquots. We took 5% egg yolk (EY,V/V) as control group, and the treatment groups were different concentration soybean lecithin (SL,m/V):10%, 20%,30%. Frozen-thawed semen was evaluated the spermatozoa motility parameters, sperm plasma and mitochondrial membrane integrity, lipid oxidative production MDA. The results showed that the total motility was not significant compared 5% egg yolk to different concentration soybean lecithin (P>0.05). 30% soybean lecithin obtained the highest local motility and lowest progress motility (P<0.05). While 20% soybean lecithin produced the lowest MDA in all the groups, and had a better sperm plasma integrity. It also found that 20% and 30% soybean lecithin were higher in JC-1⁺/PI^-, but compared with 20 soybean lecithin had no effect (P>0.05). It was concluded that 20% soybean lecithin could instead of 5% egg yolk in the cryopreservation of stallion semen.

Key words: soybean lecithin; egg yolk; semen; cryopreservation; stallion