Ten strains of male rats are commonly used for experimental study at present in Beijing. The rats’ outward appearence

stool

picture of the tongue

body temperature

and wet weight of adrenal gland

thymus gland and spleen were observed

and the function of the hypothulamus pituitary thyroid axis was determined. Results showed that the constitution of Wistar grade Ⅰ

Ⅱ

Ⅲ

and SD grade Ⅲ were basically normal. SD grade Ⅰ had the constitution of mild deficiency - cold

SD grade Ⅱhad constitution of excess - heat

CD （SD） IGS grade Ⅲ （small or big body weight） had constitution of mild deficiency

SHR grade I had constitution of mild deficiency -cold

SHR/sp grade I had obvious deficiency -cold constitution; There was a certain difference in TCM constitution among different strains

same strain with differrenct microbic grades

pure line and inbred line

and different ages in rats. It is indicated that the study on TCM crasiology in experimental animals are not only necessity

and also feasibility.