Iterative pruning of non-phenotyped non-parent animals and back-solving of their solutions followed by the genetic evaluation analysis

Many animals entering the genetic evaluation analysis do not contribute any information (non-phenotyped) and they do not receive any progeny information (not parent to any phenotyped descendants). If these animals are removed from the analysis, the number of equations to solve and the computational demands are reduced. Using an example data and the R code (the attached files; the data itself is created by the R code), it is shown how to prune the pedigree by iteratively discarding non-phenotyped non-parent animals.

The evaluation of pruned animals is necessary. However, the evaluation (i.e., breeding value and its reliability) of these animals is fully conditional to their parent(s). Therefore, their evaluation can be obtained at a much lower computational cost out of the equation system. The attached data and R code show this procedure (called back-solving).