| chronic rat |
Chronic (>90 days) |
A total of sixty healthy pure SD rats, equal male and
female, were purchased from Guizhou Laboratory Animal Engineering Technology
Center for the study. The selected rats were randomly
divided into two groups (control group, fluoride exposure group) with equal
size based on body weight using random number table method. The control group
was given tab water every day (containing fluoride less than 0.5 mg/L);
the fluoride exposure group was given sodium fluoride at 50 mg/L. Rats from
both groups were given standard animal food containing fluoride less than 6.2 mg/kg. |