The effects of three feeding management were evaluated in the winter months (CN: natural pasture; CNS: natural pasture + supplementation; CNM: improved natural pasture) and three live weight groups (light, medium, heavy) on the subsequent reproductive performance of Brangus heifers with first service to 24/27 mo old. Feeding managements showed differences in the daily weight gain (DWG) during the winter (0.261, 0.376 and 0.679 kg/day) in body weight at the beginning of the reproductive period (302.8, 317.8 and 330.7kg for CN, CNS and CNM, respectively). The pregnancy rate (PR) did not differ among the feeding managements (88.3, 93.3 and 95.0% for CN, CNS, CNM, respectively). However, CNM has resulted in lower reproduction to conception interval (IRC of 30.5 days). The feeding managements on CN and CNS resulted in reproduction to conception interval of 36.4 and 39.4 days, respectively. Live weight groups showed similar DWG (0.600, 0.612 and 0.634 kg/day) and kept the difference in body weight at the beginning of feeding managements and at beginning of the reproductive period (299.6, 316.0 and 335.6 kg for light, medium and heavy groups, respectively). Among heifers of heavy group, the pregnancy rate was higher (100%) and the time between the beginning of the reproduction - conception period (IRC), smaller (29.86 days). Light group heifers showed pregnancy rate of 91.6% and higher IRC (39.83 days), and heifers of the medium group 85.0% and 36.8 days, respectively.
beginning of reproduction-conception interval; improved natural pasture; pregnancy; supplementation
