So much of cat food advertising is from the cat's perspective. So I
 switched things up. Who else wants you keeping your cat well fed? 

A guerilla style campaign would be spread throughout the underground (the home of mice) using 3d mice models to imply that they were making their own ads.  

When the birds chip in, their work could exist as digital banners
or 'airplane' banner ads draped across aisles in stores. 

And in the streets, mini mice protests would let their tiny voices be heard.