There are tons on the web - do a search for "ascii animals" and you'll find lots!

Like
this ferret
             ;;
.~.~~;;;;;;;
\_/-\|----\\
 '  ""        "" b'ger


cat
               //
 /\_/\         //
(@.@ )_.-._//
> O < .-.   )
  |/   |/

reindeer -

    {_}
'-=\
     \\____(
    _|/---\\_
    \        \

There are tons out there!