Polypeptides associate to membrane integrity (MI) of swine spermatozoa submitted to freezing and thawing were identified. The protein profile of seminal plasma analyzed by SDS-PAGE allowed the identification of nine polypeptide bands with molecular weight ranging from 11.97 to 122.52kDa. One 26.58kDa band was associated with reduced MI (<55%). No associations among other bands and MI were observed. The 26.58kDa factor is associated with reduction of membrane integrity of swine spermatozoa after freezing and thawing.
swine; semen; protein; cryopreservation; biochemical marker