The Toxic Effect On Skeleton With High Molybdenum In Sheep

Objective：The study was carried out to investigated the toxic effect of skeletonin sheep with high molybdenum in bone density、bone biomechanical and boneelement content.Methods：Twelve healthy male small tail han sheep were randomly dividedinto3groups,4in each group. Animal models were established as follows: Group Ⅰfeed basal diet, group Ⅱ feed basal diet+30mg·kg-1molybdenum, group Ⅲ feedbasal diet+60mg·kg-1molybdenum (molybdenum source for Na2MoO42H2O). Onthe180th day, killed all the sheep, selected limb bone swatches, utilized X-rayradiography technology, dual energy X-ray radiography technology, bonebiomechanical method, atomic absorption spectrometry and so on from differentaspects to investigated the toxic effect of skeleton in sheep with high molybdenum.Results:1. The changes of bone X-ray and bone density: The bone cortex of humerus,radial, metacarpal, femoral, shin, metatarsal of group Ⅲ and Ⅱ compared with groupⅠ became thin, the bone trabecula of them were rare and the marrow area wereincreased; the average bone density of humerus, radial, metacarpal, femoral, shin,metatarsal in group Ⅲ and Ⅱ compared with group Ⅰ all had different degreedecreased; the bone density of Neck, Troch, Inter, Ward’s, Total all had differentdegree decreased.2. The results of bone biomechanical: The torsion angle of the humerus、torsion、torsional shear、humerus consistent、stress of the femoral、the strain offemoral in group Ⅲ and Ⅱ compared with in group Ⅰ had significant decrease andthe difference were both extremely significant (P<0.01), the difference between groupⅢ and Ⅱ were also significant decrease and extremely significant (P<0.01); but therewere no significant differences between group Ⅲ and Ⅱ of the stress of femoral(P>0.05).3. The results of element content in bone: Mo content in bone of humerus, radial, metacarpal, femoral, shin, metatarsal in group Ⅱ compared with in group Ⅰ hadsignificant increase and the difference was extremely significant (P<0.01), thedifference between group Ⅲ and Ⅰ was also significant increase and extremelysignificant (P<0.01), the difference between group Ⅲ and Ⅱ was also significantincrease and extremely significant (P<0.01). Cu, Mg, Fe content in bone of humerus,radial, metacarpal, femoral, shin, metatarsal in group Ⅲ, group Ⅱ or group Ⅰ allhaven’t changed much, and the differences between each other of group Ⅲ, group Ⅱand group Ⅰ all had no significant (P>0.05); Zn content in bone of humerus, radial,metacarpal, femoral, shin, metatarsal in group Ⅱ compared with in group Ⅰ hadsignificant decrease and the difference was significant (P<0.05), the differencebetween group Ⅲ and Ⅰ was also significant decrease and extremely significant(P<0.01), the difference between group Ⅲ and Ⅱ was also significant decrease andsignificant (P<0.05). Ca and P content in bone of humerus, radial, metacarpal, femoral,shin, metatarsal in group Ⅱ compared with in group Ⅰ had significant decrease andthe difference was extremely significant (P<0.01), the difference between group Ⅲand Ⅰ was also significant decrease and extremely significant (P<0.01), Ca and Pcontent in bone of shin and metatarsal in group Ⅲcompared with in groupⅡ hadsignificant decrease and the difference was extremely significant (P<0.01), but inhumerus, radial, metacarpal and femoral the difference was significant (P<0.05).Conclusion:30mg·kg-1molybdenum and60mg·kg-1molybdenum both had some toxic effectof skeleton in sheep, the results mainly showed that30mg·kg-1and60mg·kg-1molybdenum decreased the bone density of the sheep; decreased the bonebiomechanical of humerus, femoral and metatarsal; increased the bone Molybdenumcontent, decreased the Zinc, Calcium and Phosphorus content; and60mg·kg-1molybdenum had significant toxic effect in bone of sheep compared with30mg·kg-1molybdenum.