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.
Data is represented as least square means with error bars as standard errors. Symbol * indicates that day 1 is significantly (P<0.05) different from all other days.
