Feed blocks as alternative supplements for sheep and goats

This paper discusses the potential use of feed blocks as alternative supplements for stall-fed and grazing small ruminants raised under harsh environments. A background on manufacturing process of these blocks and the impact of their use in livestock feeding are reported. Trends converge to indicate that hard blocks, a mixture of agro-industrial by-products, urea, binder and preserver, improve digestion of low quality forages thereby increase body weight. Therefore, feed blocks may be considered as an alternative to promote intensive use of numerous agro-industrial by-products and to overcome nutritional constraints. A positive effect of block enriched or not with microelements and vitamins on reproductive performance of ewes was demonstrated. Another potential role of feed blocks is their use as efficient carrier of tannin-neutralising reagents (e.g. polyethylene glycol) to valorise tanniniferous shrubs and trees. Worth noting that these blocks may be used also to vehicle some anthelmintic medicines for small ruminants to control gastrointestinal nematodes. Feed blocks may reduce the use of concentrate feeds, thus reduce feeding cost and increase farmer's income. In addition to their nutritional and economical benefit, the success of feed block technology depends on its adoption by smallholders. Therefore, the active participation of farmers in the evaluation and transfer of feed block technology targeting their specific conditions is highly recommended. (C) 2003 Elsevier B.V. All rights reserved.