An experiment was conducted using Bovans White layers to investigate the effects of 30% whole-wheat inclusion in a standard layer diet supplemented with xylanase, on laying performance, digestive organs and ileal mucosa development. Three dietary treatments were used: 1) control diet (30% ground wheat); 2) 30% whole wheat; 3) whole wheat+wheat xylanase. Xylanase was added to whole wheat at 150g/ton. Including the pre-experimental period the trial lasted for 13 weeks. Xylanase supplementation to whole wheat significantly (P