اثر ویتامین C بر تراکم مواد معدنی استخوان و خصوصیات پوسته تخم مرغ در پیک تولید مرغان تخمگذار

Abstract

The aim of current study was to determine the effects of vitamin C on bone mineral density (in terms of osteoporosis), eggshell quality and investigation of correlation between these factors in laying hens reared under normal condition. One hundred and ninety two 24 - weeks - old laying hens diet was supplemented with 4 levels of vitamin C (0, 250, 500 and 750 mg/kg diet). The experimental design was completely randomized (CRD). Egg production, metatarsus bone mineral density (BMD) index and correlation coefficient between BMD index and some eggshell characteristics were determined. Egg weight, egg mass, hen-day egg production and eggshell quality (shell thickness, shell weight and shell percentage) were not influenced by vitamin C (p>0.05). The BMD index of metatarsus also did not change by vitamin C utilization at 38-weeksold (p>0.05). No significant correlation was found between BMD index and shell characteristics (p>0.05). However, positive correlation was observed between BMD index and egg weight also between BMD index and hen-day egg production (p<0.05). The correlation between specific gravity and eggshell characteristics was significantly positive (p<0.01). The results of this study showed that vitamin C does not affect on bone mineral density and eggshell quality, under normal condition. In addition the rate of egg production had low effects on bone mineral density. Finally bone mineral content is rarely used for eggshell formation