Toxins in temperate grasses—implications and solutions

The toxicity of several important temperate grass species is reviewed. Identification of N‐methyltyramine in Phalaris aquatica cultivars provides a possible new etiology for the sudden death syndrome associated with this pasture species. The spread of the plant‐pathogenic, toxigenic bacterium Clavibacter toxicus to new grass species and recent episodes of poisoning in livestock grazing C. toxicus ‐infected grasses raise the possibility that this poisoning disease may affect a wider range of pastures in the future. While livestock, especially ruminants, are well adapted to detoxifying poisons they ingest, there are examples of secondary poisoning of humans through the consumption of animal products. The issue of transfer of poisonous plant components to animal products for human consumption needs to be investigated where a real risk to human health is perceived. Elimination of toxins from pasture species provides the best solution to poisoning. Where this is impracticable, vaccination and enhanced detoxication in the rumen may be options for protecting livestock.