Transcript:
Now you might say he's just a small mouse.. But give him a mic and he's a tall mouse.. A let-it-go-and-give-it-all mouse.. A standup straight-and-never-crawl mouse! I gotta say, I'm a traditionalist.. But I am kind of digging the rap/howling blend here..
My guess is Louie is howling because the mouse is rapping!