Characteristics of linkage disequilibrium in North American Holsteins

A minimal sample size of 444 and 55 animals is required for an accurate estimation of LD by /D'/ and r2, respectively. The use of only maternally inherited haplotypes is recommended for analyses of LD in populations consisting of large paternal half-sib families. Large heterogeneity in the pattern and the extent of LD in Holstein cattle was observed on both autosomes and the X chromosome. The extent of LD was higher on the X chromosome compared to the autosomes.