EN
Effect of antinutritive factors in the feed (phytic acid, nonstarch polysaccharides) and kind of trace element forms (inorganic vs organic) was presented on the basis of literature review. Phytic acid, through formation of indigestible complexes with microelements, significantly decreases its utilization by the organism. Also non-starch polysaccharides showed of ten similar influence. Organic forms of trace elements generally are characterized by higher bioavailability than their inorganic forms.