Disclosed is a method of increasing the genetic progress of a line or breed of swine comprising the steps of: Collecting a semen sample from a boar from said line or breed； sorting said semen sample into at least two subpopulations of sperm cells, wherein at least 80% of a first subpopulation bears X-chromosomes or Y-chromosomes； Inseminating a sow from said line or breed with sperm cells from said first subpopulation； producing offspring from said sow； Calculating a selection index for one or more of said offspring； and Selecting one or more of said offspring having a higher selection index compared to the average selection index for said line or breed to breed with a swine from said line or breed so as to increase the genetic progress of said line or breed.
