Effect Of VD₃ On Bone Metabolism Of Young Layer And A Study Of Chinese Traditional Medicineon Prevention And Cure Of Osteoporosis In Cage Layer

Effect of VD3 on Bone Metabolism of Young Layer175 10-wk-old ISA hens were randomly allocated to one of five levels ofVD3:0~ 100.. 200.. 500 and I000IU per KG diet respectively. Birds were fed the diets for 10 weeks during which blood sample were collected every 2 weeks to analyze for blood calcium, blood phosphorus ,akkaline phosphatase(AKP), bone Gla protein(BGP), calcitonion(CT), tibia bone mineral content(BMC) and body weight were mensurated at the same time At beginning and end of the experiment, five hens of the five levels dietary VD3 groups were killed and tibias were collected for histopathological research.There were no significant variety among different dietary VD3 groups in blood calcium, phosphorus, CT(P>0.05). But the lack or excess of dietary VD3 can lead to declining of BMC, and the variety was significant (P<0.05). AKP of 2001U group was significantly low compared to 0, 500 and 1000IU groups(P<0.05). BGP was negative correlative to VD3 in diets. The research based on histopathological and histomophometry revealed that hens?cortex bone and bone trabecula was normal at the beginning. At the end, there were different grades resorption cavities on the surface of cortex bone in the groups of lack or excessive VD3.In conclusion, no matter what the VD3 is lack or excessive will damage to the bone of young layer;2001U-VD3/Kg diet is best for the growth of young layer.