Dentition based age had a low agreement with Chinese ossification maturity for Luxi and Qinchuan cattle no more than 24 months old and a high agreement for cattle above 24 month onth.

Investigation on the effect of fissure sealing on prevention of dental caries in six-year-teeth;

Digestive tract of Gyllotalpe Unispina Sausure had special histology, there were protruding long crest on all inner wall Of digestive tract and thick short tooth in its cavum oris and pharynx, some compact thin long thom lied on gastric caecus and preventriculus, there are microvilli on its esophagus, crop and postintestine, many blunt thom were on the rectum.

The expressions of plane and space conjuration gear forms and meshing line of a single thread twin screw pump are derived on the basis of spatial meshing theory, and the equations for original gear forms and space spiral plane are given.