Replacing Dietary Corn with Bakery By-products Supplemented with Enzyme and Evaluating Performance of Laying Hens

The objectives of this experiment were to investigate effects of dietary replacement of maize with bakery by-product (BB) with or without enzyme supplementation on the performance of laying hens and egg quality characteristics. A total number of one hundred and eighty 87-week-old Hy-Line Leghorn hens, with an average laying rate of 56.7±3.8% (late production phase) and 1470±14 g live body weight, were weighed and distributed between 30 cages with almost same egg production (EP) level among the cages. Six iso-caloric and iso-nitrogenous diets were formulated (ME=2900 kcal/kg and crude protein= 15.20 g/100 g diet) based on the catalogue of Hy-line. The experiment was conducted as a 3×2 factorial arrangement of treatments including three replacement levels (0, 50, and 100%) of corn with dried bakery byproduct replacement) and enzyme supplementation (0 and 0.06 g/100 g diet of Hemicell, a commercial β-mannanase-based cocktail enzyme product). Each of 6 experimental diet fed hens in 5 replicates with 6 birds per each replicate (cage). The hens’ performance including hen-day egg production% (EP), egg weight (EW) and feed intake (FI) was measured for 4 weeks and egg mass (EM, g/hen/day) as well as feed conversion ratio (FCR, g feed: g egg) was calculated. The data was analyzed based on completely randomized design using GLM procedure of SAS. Replacing dietary corn with BB had no significant effect on egg production (%), except in week 2. Egg production in group of 100% corn-replacement in week 2 was lower than the other dietary groups. However, the overall EP for weeks 1-4 was not significantly affected by replacing dietary corn with BB. In addition, EM and FCR were not significantly affected by dietary treatment. Egg weight was affected by dietary cornreplacement in weeks 1 and 2; however, no significant difference was found in weeks 3 and 4. Egg quality characteristics were not affected by dietary treatment. Enzyme supplementation had no significant effect on performance of hens and egg quality traits. From the results of this experiment it can be concluded that dietary corn can be totally replaced with bakery by-products with no adverse effect on performance and egg quality. In addition, β-mannanase has no beneficial effect on performance of hens fed on cornor bakery by-productbased diets.