NR 38. Heifers management supplementation in savannas plains conditions. I. Reproductive behavior to two ages supplemented with multinutritional blocks

Abstract

A group of 42 contemporary zebu crossbred dual-purpose heifers, grazing Trachypogon sp. were randomly assigned to 3 treatments: (T1), group control with commercial minerals (normal farm management); (T2) and (T3) groups that had received supplementation 22 and 30 months of age respectively, with multinutritional blocks (MB) of whole cottonseed (Gossypium hirsutum). Age and the live weight to first detected ovarian activity was significantly (P<.05) in T2 with respect to T1 (1212.15 ± 38.32 vs 1354.0 ± 40.18 days) ; (309.67 ± 9.45 vs 275.82 ± 9.91 kg ). Greater differences were observed in age at first calving, where the T2 heifers calved significantly early (P<.01; P<.05) than the T1 group (1481.55 ± 55.86 vs 1655.31 ± 39.45), and the T3 heifers (1481.55 ± 55.86 vs 1607.22 ± 34.54), respectively. The results indicate that strategic supplementation with (MB) was beneficial to heifers in savannas, and permitted a reduction in first calving age, a conditions important in defining low productivity in the tropical areas.