Selection scheme of the Segureña breed of sheep

Resumen

The breeding program of the Segureño breed of sheep is discussed, standing out the main difficulties and achievements for the last three years. The program is presented as a model for the genetic improvement of local breeds used in hard areas of Spain. A total of 151 herds and 36000 animals compose the selection nucleus. The response to selection in this base population affects directly, the animals that belong to the nucleus, and indirectly, around 1.3 millions of animals which is about the whole census of the breed. Up to present, the selection objectives of growing and prolificacy have been almost completely developed. However, intense difficulties have been faced on selecting for conformation. The score been used, as a unique dependent variable, does not fulfill the normality properties commonly assumed in the analysis. On the whole, about 80% of the program has been developed.