The influence of the early weaning, on average 77 days after the birth, or the conventional weaning, on average 147 days on beef heifer development was evaluated. One hundred and sixty-one Braford calves, born in 2004, 2005 and 2006 were kept after weaning on cultivated summer (Pennisetum americanum) and winter/spring (Avena strigosa Schreb and Lolium multiflorum Lam) cultivated pastures. Body weight, daily Body weight gain and body condition were assessed every 28 days. There was interaction between weaning age and year for body weight and weight gain. Early weaning did not influence body weight but the body weight was smaller at 147 days in the animals born in 2005 and 2006. The avegage daily gain between the weaning ages was similar in the three years for early weaning (0.538, 0.477 and 0.472 kg, respectively), but increased significantly in the conventional weaning as the years progressed (0.516, 0.704 and 1.040 kg respectively). The average daily weight gain on Avena strigosa + Lolium multiflorum pasture was similar for both treatments. The weight at the beginning of the reproduction period for early weaned heifers in 2004 (283.4 kg) was higher than in 2005 (260.7 kg), while for conventional weaning there was no difference between years (272.9 and 263.8 kg, respectively). The body condition at the beginning of the reproduction period was affected by the year of observation. Calf age was positively correlated to weight at conventional weaning (r = 0.510) and beginning of the reproduction period (r = 0.491). Both weaning ages showed the possibility of mating beef heifers at 14/15 months of age.
body condition; conventional weaning; early weaning; weight gain
