Ricca, 1993. Livest. Res. Rural Dev., 5 (2): 31-38

An experiment was carried out to evaluate the influence of multinutrient blocks (MB) on live weight (LW) gain of young bulls of 235 kg initial LW grazing sorghum stubble during the dry season. Thirty two animals were divided in two groups of similar weight and continuously grazed two paddocks of 14 ha for 21 weeks. One group was offered MB in four places and the other received a mineral mixture (MM). Both groups were rotated between paddocks every two weeks to minimize the effect of plot. The MB had 32.3% crude protein, and the main ingredients were 40% chicken manure, 32.5% molasses, 10% lime, 5% salt, 5% minerals, 5% urea and 2.5% ground hay. LW gains of animals offered MM and MB were 1.18 and 1.33 kg/day during the first eight weeks (P<0.05) and 0.30 and 0.31 kg/day during the remaining 13 weeks (P>0.05). The higher response to MB at the beginning of the trial was associated with a high availability of stubble of low nitrogen content. The reduction of stubble availability towards the end of the trial limited the LW gain response to MB.