Effects of different dietary vitamin combinations on the egg quality and vitamin deposition in the whole egg of laying hens

The experiment was conducted to evaluate the effects of different dietary vitamin combinations on the egg quality and vitamin concentrations in the eggs of commercial laying hens. A total of 1,800 25-week-old Lohman pink-shell hens were randomly assigned to four dietary vitamin treatments as follows: NRC(1994) level, NRC (1994) level with Hy.D® (25-hydroxy-cholecalciferol), Local level (current average industry level in China) and OVN® level (optimum vitamin nutrition level), with 10 replicates per treatment and 45 layers per replicate. Hens were housed in commercial laying cages with three ...