Effect of Eggshell Power on Calcium Status in Rats

Objective To investigate the effect of eggshell power on growth,calcium absorption and utilization in rats and to compare the differences in effect of supplemented calcium from eggshell power,bone power and calcium carbonate.Methods Weaning rats with half male and female were fed with Ca-deficient diet for three weeks,then the rats were randomly divided into four groups(Ca-deficient,eggshell power,bone power and CaCO₃) by their weight.These rats were fed for 12weeks.During the fifth week,3 days calcium metabolism test was done.Results The results showed that bone calcium,bone mineral density(BMD),bone mineral content(BMC) and femoral bone weight were obviously better in supplemented Ca groups than in the Ca-deficient group(P<0.01 or P<0.05).The bone calcium significantly increased in eggshell group than in CaCO₃ group(P<0.05).However,the differences of BMC,BMD and femoral bone weight were not found in supplemented Ca groups.The absorption rate and retention rate in Ca-deficient group were much higher than in supplemented Ca groups(P<0.01).Although the absorption rate and retention rate in eggshell group were the highest among supplemented Ca groups,statistical significant difference was not found.The lead content in bone power exceeded the state standard.Conclusion It was concluded that the effect of supplemented Ca by eggshell was better than that by CaCO₃.It is valuable to do further study on the action of eggshell power owing to its cost-efficient.