Influence of silage contamination by soil upon trace elements availability in sheep.

The influence of soil contamination in silage has been studied in two successive balance trials realized with 12 growing lambs (27 kg). A perennial Rye Grass at the first cycle was offered alone or contaminated with 5% of acid brown soil issued from altered granit rocks. Voluntary intakes and dry matter digestibility were lowered. Similarly copper, zinc and manganese digestibility dropped sharply in spite of a diet enrichment in these elements by the soil.