Statistical analyses were performed with the software SPSS
16.0. One-Way Analysis of Variance (ANOVA) was used to detect
the difference of mass (body mass and intestine mass), body size
(total body length, tail length, and hind-limb), mortality and TH
levels between controls and experimental treatments at metamorphic
climax (stage G42). ANOVA was also used to compare statistically
differences of Dio2 and Dio3 expression at mRNA levels within
given tissues. Kaplan–Meier analysis was conducted on cumulative
metamorphosis percent among the various treatment groups with
monitoring days. The criterions were defined as statistically significant
when p 6 0.05 or as highly significant when p 6 0.01 in all
cases.