Increasing the productivity is one of the main objectives in livestock breeding programs. Traits such as milk production, milk fat content, disease resistance and number of offspring are economically important for both North American farmers and farmers in developing countries. Traditional breeding methods have led to better production but this is slow and not easily attainable for quantitative traits controlled by multiple genes with low heritability. Selecting critical alleles at these loci using new genomic approaches will help farmers with their breeding programs.