Another study was conducted to determine the effects of including 15% crude glycerin in the feeding of commercial layers. The crude glycerin source (3042 kcal / kg AMEn (determined previously through a balance study), 8.3% moisture, 82.0% glycerol, 0.79% crude fat, 1.21% sodium and 16 ppm of methanol) were fed to 216 Babcock Brown laying hens randomly assigned to one of six crude glycerin treatments (0, 3, 6, 9, 12 and 15%). The results showed that the inclusion of crude glycerin levels up to 15% did not affect hen performance in terms of egg production (94.5 ± 7.0%) or egg weight (67.5 ± 2.4g); however, feed intake decreased linearly with the level of inclusion of crude glycerin in the diet. Layers supplemented with 12 or 15% of crude glycerin consumed 4.6% less feed (P < 0.05) compared with the control group and 3% of supplementation.