The influence ofthe 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 andsixty-one Braford calves, born in 2004, 2005 and 2006 were kept after weaningon cultivated summer (Pennisetum americanum) and winter/spring (Avenastrigosa Schreb and Lolium multiflorum Lam) cultivated pastures.Body weight, daily Body weight gain and body condition were assessed every 28days. There was interaction between weaning age and year for body weight andweight gain. Early weaning did not influence body weight but the body weightwas smaller at 147 days in the animals born in 2005 and 2006. The avegage dailygain 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 theconventional weaning as the years progressed (0.516, 0.704 and 1.040 kg respectively).The average daily weight gain on Avena strigosa + Lolium multiflorumpasture was similar for both treatments. The weight at the beginning of thereproduction period for early weaned heifers in 2004 (283.4 kg) was higher thanin 2005 (260.7 kg), while for conventional weaning there was no difference betweenyears (272.9 and 263.8 kg, respectively). The body condition at the beginningof the reproduction period was affected by the year of observation. Calf agewas positively correlated to weight at conventional weaning (r = 0.510) andbeginning of the reproduction period (r = 0.491). Both weaning ages showed thepossibility of mating beef heifers at 14/15 months of age.
