Micro-mineral profile in different grassland species

Summary

The aim was to investigate the micro-mineral profile of herbage as affected by grassland species, cutting time and seasonality and in relation to dairy cow requirements. The different grassland species were grown and harvested in mixtures with one grass and one legume for two growing seasons. The species turned out to have very individual mineral profiles, not influenced by year. Among the legumes red clover (Trifolium pratense) had high concentrations of Co, Cu and Zn, white clover (Trifolium repens) of Mn and Fe, lucerne (Medicago sativa) of Se and lotus (Lotus corniculatus) of Co, Mn, Zn and Fe. Among the grasses perennial ryegrass (Lolium perenne) generally had the highest concentrations of all the micro-minerals. Hybrid ryegrass (Lolium hybridum) had slightly lower concentrations than perennial ryegrass for all minerals. Meadow fescue (Festuca pratensis) had lower concentrations still, and timothy (Phleum pratense) had, with the exception of Zn, the lowest concentrations. In general, the mineral concentrations were higher in summer than in spring growth. During the growth Cu, Zn and Fe concentrations decreased, whereas Co, Se and Mg were unaffected. It was concluded that a mixture of red clover and perennial ryegrass had the best profile of micro-minerals for cattle feeding.