EFFECT OF ADDING VITAMIN D3 AND VARIOUS PARTICLE SIZE OF OYSTER SHELL TO DIETS IN CALCIUM AND VITAMIN D3 CONCENTRATION, EGG SHELL AND BONE BREAKING FORCE IN LAYING HENS

This study was conducted in the poultry farm belong to Department of Animal Production at College Agriculture, University Anbar, from 20/7/2021 15/10/2021, show role vitamin D3 and multi particle size oyster shells providing needed calcium for laying hens order manufacture eggshell throughout hours day its impact on shell quality bone health. one hundred-eight Lohman Brown hens, 43 weeks age, were distributed randomly nine treatments, four replicates each treatment three replicate. The experimental treatments as follows: T1/ control diet without any additives, T2/ source 50% limestone + less than 1 mm 4000 IU kg-1, T3/ +50% 1-2 T4/ 2-3 T5/ Limestone 3–5 Vitamin T6/ Calcium 8000 T7 / +Vitamin T8 T9/ 3-5mm kg-1. results showed a significant increase (P≤0.05) levels blood plasma fifth, sixth, seventh, eighth ninth treatments. indicated Significant level tibia breaking strength content force trait fourth,