Reputation: 785The Call of the Wild.
Whitefang.
Both by Jack London.
Also, The Wind in the Willows.
Giraffe by J.M. Ledgard. It's a more realistic novel with animal protagonists (Giraffes). It's absolutely heartbreaking and very beautifully written.
Animal farm.
it does surprise me that no one has mentioned it yet, hell i'm a tad suprised i didn't mention it right off the bat.