Abstract: ObjectiveTo observe the effects of high and low iodine on the growth development of pregnant mice and on growth and physical ability development of young mice.MethodsThe mice were divided into three groups,high iodine,low iodine and middle iodine group by randomized block design.The goiter models of high iodine and low iodine were replicated in KM mice by drinking water containing high iodine and low iodine.The body weight changes of pregnant mice during pregnancy and postnatal mice were observed,the movable endurance was evaluated by swim exhausting experiment.Results(1)High iodine and low iodine both significantly retarded the body weight's increasing velocity of the pregnant mice compared to that of middle iodine mice from the 9 day of pregnancy to the end (P<0.05).(2)The body weight of the progenies of low iodine group was remarkably lower than that of middle group from weaning to 3 months,but no remarkable change of body weight was observed between middle iodine and high iodine groups.(3)The time of the swim exhausting of high iodine mice was longer than that of middle iodine mice which in turn was logner than that of low iodine mice,showed a significantly difference between low iodine group and high iodine group,no change was observed between the other groups.High iodine and low iodine retarded the body weight's increasing velocity of pregnant mice,simultaneously low iodine retarded the growth development and lowered the physical ability of progenies.ConclusionIt indicates that the effect of high iodine on growth development is mainly in the key time of embryo development.