Performance data on fertility of ewes, pre-weaning mortilaty of lambs and productivity were collected during two years from 24 village flocks in Cnetral Anatolia. The data included flocks with sheep from the Akkaraman and Merino breeds and their crosses. The overall means for lambing rate, weaning rate, twining rate and pre-weaning lamb mortality were 92.1%, 89.8%, 4.8% and 6.9%, respectively. The fertility traits were significant effected by genetic group, area were the flock was located and age of ewe and the lamb mortality by the first two effects. Merino ewes had a significantly higher fertility and twinning rate than the Akkaraman breed. Three types of productivity indices relating the litter weight at weaning to the weight of the dam were calculated and analyzed by the least-squares method. Systematic effects of flock, sex of litter and age of dam were highly significant (p

Performance data on fertility of ewes, pre-weaning mortilaty of lambs and productivity were collected during two years from 24 village flocks in Cnetral Anatolia. The data included flocks with sheep from the Akkaraman and Merino breeds and their crosses. The overall means for lambing rate, weaning rate, twining rate and pre-weaning lamb mortality were 92.1%, 89.8%, 4.8% and 6.9%, respectively. The fertility traits were significant effected by genetic group, area were the flock was located and age of ewe and the lamb mortality by the first two effects. Merino ewes had a significantly higher fertility and twinning rate than the Akkaraman breed. Three types of productivity indices relating the litter weight at weaning to the weight of the dam were calculated and analyzed by the least-squares method. Systematic effects of flock, sex of litter and age of dam were highly significant (p