NOTE ON THE OPTIMUM NUMBER OF DAUGHTERS PER SIRE TO MAXIMIZE THE GENETIC PROGRESS FOR LITTER SIZE IN SEGURENA SHEEP

Litter size performances of more than 6000 ewes, distributed in 20 her ds connected through artificial insemination, were simulated during 21 consecutive lambings. Three different structures of progeny-tests wer e considered. The objective was to assess for the adequate number of d aughters per tested sire, for a correct prediction of its litter size breeding value in order to maximize the genetic progress for this trai t in the Segurena selection scheme. Results showed that when testing s ires with about 30 daughters each one and according to the given param eters considered, the maximum genetic progress is obtained.