red=$(tput setaf 1)
green=$(tput setaf 2)
blue=$(tput setaf 3)
reset=$(tput sgr0)

This is ok:
echo foo|cowsay
 _____
< foo >
 -----
        \   ^__^
         \  (oo)\_______
            (__)\       )\/\
                ||----w |
                ||     ||

Here foo is green as expected but the header and footer of cloud is to long:
echo ${green}foo${reset}|cowsay
 ________________
< foo >
 ----------------
        \   ^__^
         \  (oo)\_______
            (__)\       )\/\
                ||----w |
                ||     ||