The purpose was to evaluate the reproductive performance of woolless ewes due to the feeding management of offsprings and weaning age in addition to measuring the effect of gender on weight gain of lambs. Sixty-four Santa Inês crossbred ewes were distributed in a completely randomized design in a factorial 4 x 2 x 2 - four weaning ages (56, 70, 84 and 98 days), sex and feeding management of the offspring, each treatment with four replications. The ewes were managed with the offsprings at the foot in 14 paddocks of 1,5 or 2,0 hectares, formed with Brachiaria humidícola. The offsprings were born by single birth, of Santa Inês pure of origin (PO). After the weaning of all groups, sixty-four lambs (32 males and 32 females) were randomly assigned in individual stalls and confined for 30 days. The comparison of the parameters was carried out by the adjustment of the simple linear regression model. It was verified over time addiction of the offspring feed management of + 3,7% (P<0,05) for the calving intervals and of + 1,4% (P<0,05) for the service period. There was increasing linear effect (P<0,05) of weaning age on calving intervals and service period. It was verified over time, addiction of the offspring sex of + 2,0% (P<0,05) for the calving intervals and + 0,8% (P<0,05) for the ewes service period. It was observed over time addiction of sex of + 35,2% and + 36,9% (P<0,05), respectively, for the daily weight gain of lambs from birth to weaning and post-weaning in feedlot. The supplementation of the offspring in private feeder and the anticipation of the weaning age reduce the calving intervals and the service period of woolless ewes in Brachiaria humidicula pasture. The offspring sex is the source of variation in the analysis of reproductive efficiency of ewe's mat rices and in the weight gain of Santa Inês crossbred lambs from birth to weaning, and after weaning.
ewe; body development; reproductive efficiency weaning age
