An official website of the United States government
Here's how you know
Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Long–Evans rats at P19 and P38. Both height (A) and length (B) differ dramatically between these age groups. Behavioral testing conditions must account for differences in size and step length in relation to the animal’s age.