Results all the experimental groups of rat had got colloid goiter and the higher concentration of iodine in food,as the lower of height of thyroid cell and the gigger of area of follicle.

• 结果实验组出现了胶质性甲状腺肿，不典型增生出现的百分率增加，甲状腺细胞的高度随饲料含碘量的增加而逐渐降低；