Factorial experiments were conducted between 2001 and 2006 to investigate the effect of temporary weaning (about 12 days just prior to breeding) and supplementation with a source of cheap energy for about 20 days at the begin of breeding. With a total number of more than 300 cows evaluated, it was determined that both temporary weaning and supplementation with rice bran significantly increase pregnancy rates. However, the most important factor is temporary weaning. Complete separation of mothers and calves during temporary weaning resulted in highest pregnancy rates and highest levels of ovarian activity. Significant positive effects on ovarian activity and follicular development were observed. Negative effects on calf development were not observed, despite lower milk production persisting after end of temporary weaning. It was determined that the cow optimum condition score for this procedure was about 3.5 on an eight-point scale. Our results are now used to develop a pasture/range management system that optimizes these interventions by designing stocking rates that have the highest probability of maintaining primiparous cows at about 3.5 BCS. The implications for reproductive management in extensive beef cattle production systems are discussed.