The invention relates to methods of increasing genetic merit of swine by establishing a plurality of mating subtypes for a line of swine, and determining a percentage of progeny that are male for each of the mating subtypes, or a percentage of progeny that are female for each of the mating subtypes, that would result, relative to a control, in an increase in genetic merit in the line； the invention further relates to sorting a sperm cell sample from a male swine in one of the mating subtypes into one or more subpopulations of sperm cells, wherein a majority of sperm cells in a subpopulation of sperm cells bear X chromosomes or Y chromosomes, and inseminating one or more female swine in the one of the mating subtypes with the subpopulation of sperm cells to achieve the percentage of progeny that are male, or the percentage of progeny that are female, determined to increase genetic merit relative to the control.
