Journal of Animal Science, Vol 71, Issue 5 1136-1141, Copyright © 1993 by American Society of Animal Science

JOURNAL ARTICLE

The contribution of progeny of uncertain paternity to the accuracy of sire evaluation

T. R. Famula
Department of Animal Science, University of California, Davis 95616-8521.

Recent advances in statistical methodology now permit the genetic evaluation of animals with uncertain pedigrees. Although widescale practice of these techniques is not likely, implementation will never occur until we characterize the effect of uncertain pedigrees on the accuracy of animal evaluation. This work develops the framework for such a characterization, illustrating the contribution of uncertainly identified records to accuracy of evaluation through a hypothetical example. The effect of including records of uncertain paternity is greatest for sires with few certainly identified progeny. Thus, young sires stand to benefit the most from the inclusion of progeny records with uncertain paternity. In general, as the level of uncertainty in the data is replaced by the inclusion of progeny with certain paternity, the accuracy of evaluation increases. However, situations do arise in which the accuracy unexpectedly declines with the addition of progeny records with certain paternity.