Protein Profiles in Seminal Plasma of Iraqi Buffalo Bulls (Bubalus bubalis) Associated with Fresh and Cryopreserved Semen Quality

Abstract

This study was undertaken to identify some protein profiles in the seminal plasma of Iraqi buffalo bulls and their correlation to the quality of fresh and cryopreserved semen. Semen was collected from eight buffalo bulls and divided according to the percentage of sperm individual motility into two groups. The first group (n=3) included good semen quality, while the second group (n=5) included poor semen quality. Seminal plasma was extracted from each semen sample by centrifugation and seminal proteins were resolved by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Nine types of protein bands were observed in the seminal plasma of the buffalo bulls belonging to good semen quality, ranging from 10-68 kDa. The most abundant proteins in the overall presence of proteins in seminal plasma were 10 (100%), 14 (100%), 20 (100%), 26 (100%), 34 (100%), and 43 (37.5%) kDa. On the other hand, 14 types of protein bands resolved for the poor-quality semen, ranging from 10-155 kDa. The most abundant proteins in the overall presence of proteins in seminal plasma were 10 (100%), 14 (100%), 20 (100%), 26 (100%), 34 (87.5%), 130 (50%) and 155 (50%) kDa. A significant negative correlation was noticed among proteins with molecular weights of 28. 88 ± 3.26, 22.50 ± 2.85, and 12.00 ± 1.15 kDa, and the percentage of sperm individual motility and plasma membrane integrity. Moreover, there was a positive significant correlation between proteins whose molecular weight 22.50 ± 2.85 kDa and the percentages of total abnormalities and normal sperms. In conclusion, the identification of seminal proteins may be a useful tool in the future evaluation of spermatozoa and the prediction of fertility in Iraqi buffalo bulls.