Parallel Algorithm for Sorting animal Pedigrees

In many analyses of animal genotype with the methods of quantitative genetics there is a need to account for relationships among individuals. Incorrectly calculated relationship coefficients may lead to biased estimates. The number of software packages exist which deal with that problem; however, in many of them it is assumed that pedigrees of the individuals are sorted chronologically, but in real data sets – containing information on traits and pedigrees – birth dates are often missing. In extreme cases, when (almost) no birth dates are present, the ordering must be made by comparing – at least once – each pair of individuals separately, since it is not sufficient to compare adjacent elements in order to check whether the data set is sorted. Two versions of parallel computer programs were compared, with constant or variable distance between elements of compared pairs. The results indicate that the second algorithm is more efficient.