Currently sorting mammalia sperm is limited due to the damage it inflicts on sperm and costs and time associated with it are unrealistic. But the ability to sort sperm and be able to determine gender based on sperm can have huge implications to large farms and is desirable.  Sex-specific markers are needed to improve current methods and develop a working sperm sorting system. This project uses aptamers to help detect molecules. Tests were carried out to get aptamers to bind to boar sperm, and a high binding efficiency was achieved. Assessment of the aptamers found that they were in both the nuclear and cellular extract. Aptamers were then selected to pre-sorted bull sperm. The selection was monitored and then assessed. X-aptamers were found to have more binding ability than Y-aptamers.