Upgrading tannin-rich forages by supplementing ruminants with polyethylene glycol (PEG).

The paper reviews the scientific information concerning the utilisation of tannin-rich forages by livestock and examines methods to improve it. Findings on the impact of tannins on diet selection, forage intake and livestock performance are presented. The paper elaborates on the application of polyethylene glycol (PEG) in mitigating the adverse effects of tannins and the potential improvement in livestock production. The use of PEG as part of a regular management scheme, including self-regulation of its consumption by the animals, is discussed based on the findings of controlled and field experiments. Topics for future research on relationships between livestock-forage-PEGenvironment-economy are also defined