Effects of Supplementation of 25-Hydroxyvitamin D3 as a Vitamin D3 Substitute on Performance, Bone Traits, and Egg Quality of Laying Hens from 1 Day to 72 Weeks of Age

This experiment was conducted to explore the effect of long-term supplementation 25-hydroxyvitamin D3 (25-OHD) as a vitamin (VD3) substitute on performance, bone traits, and egg quality laying hens from 1 day 72 weeks age. In total, 900 one-day-old Lohman pullets were randomly allotted into three dietary groups (three treatments × 15 replicates 20 birds per replicate): VD3 2800 IU/kg; 25-OHD 69 μg/kg; 125 μg/kg. At end 20th w, five each group selected feed same D diets, used during rearing stage (1–20 w) until w. The result showed that μg/kg treatment had lowest average daily intake (ADFI) at 1–8 or 1–19 body weight 8 gain between w shank length 4 (p < 0.05). lower 7 compared with treatment. in reached maximum (about 103 mm) about 18 For femur diameter 0.001) plumpness = 0.002). tibia strength 10 0.023) keel 0.046), However, both greater 0.006), IU/kg No difference performance observed among all treatments. overall (21–72 ADFI significantly than 0.030). 60 eggshell thickness 0.012) proportion 0.022), significant differences parameters 50 70 general, supplementary doses early sufficient maintain growth development pullets. Feeding higher level (125 μg/kg) resulted reduced period, but improved late period.