Wistar rats were fed a basal stabilized-rice bran diet (B), and five additional ones, fortified to supply either 50 or 100% of zinc and calcium requirements, and a combination furnishing 100% of both minerals. Another diet supplemented with the complete mineral mix (MM) was also used. Results show that the low feed efficiency of B was maximized either by supplementation with MM, or by supplementing bran with 50010 of the zinc requirement. Attempts to compensate for the low calcium content of bran by supplementation with 50 or 100% of the mineral requirement, did not increase either feed efficiency, growth or liver zinc. These data confirm that only about 11% of zinc contained in bran is nutritionally available and that supplementing with calcium is detrimental, indicating that this by-product is not a recommendable source of minerals. (C) 2002 Elsevier Science Inc. All rights reserved.211214931500