Interaction among xylanase (XL) level, amino acid (AA) density (10% difference between low and high level), and additional fat (AF) postpellet (0, +1.17%) in corn-soybean diets with dried distillers grains with solubles for Ross 708 male broilers on feed conversion ratio (g:g) from 1 to 42 d of age. Pooled SEM = 0.005, CV = 1.54%, P = 0.003. a–c Means in bars not sharing a common superscript are significantly different (P < 0.05) by Tukey's test. Means represent 6 replicate pens of 22 broilers each per treatment.