The title pretty much says it all. The only zombies I remember seeing or hearing about are human. Any animals (or plants) that are zombies? How do they behave?
Here’s a cite for the idea that rabies (spread by animals) inspired the idea of zombies. It’s also been associated with vampires and lycanthropy.
Unfortunately the last time I read it I was ten, and that was over twenty years ago. I can’t remember how the animals behave, but it wasn’t the way you’d want them to.
I don’t recall exactly, but I think Piers Anthony’s Xanth series has zombie animals of all types. Xanth is a very fantastical universe, so zombie animals aren’t all that distinctive in that setting.
Sally, the zombie Tyrannosaur from the Harry Dresden novel Dead Beat. Dresden rides her into battle against a horde of human zombie; it goes poorly for them. Plus, she eats a ghoul.
Resident Evil (The movie) had some zombie dogs; Resident Evil (the games) have many, many critters in various forms of mutated by various zombie-like viruses.
I don’t know if*** I Am Legend ***counts as a zombie film, but in Will Smith’s version, the “Dark Seekers” (what they call the zombies) have pet dogs who seem to be infected.
For bonus points, the first zombie in Xanth was a frog; having thus discovered his zombie-making powers, the Magician in question promptly started helping folks out by “making zombie animals to guard their homes, or fight their battles” – and of course eventually built himself a big fine retinue of zombie servants: zombie people, sure, but also everything from zombie wolves and zombie bats to a zombie serpent and even a zombie tree.
(And like the man said, it’s an over-the-top fantasy setting, so the Zombie Master of course set himself up with a zombie swamp monster to guard his moat, plus a zombie ogre to pitch in on land, and a zombie roc to help out in the sky…)
Not quite the same thing, but in Harry Turtledove’s The Case of the Toxic Spell Dump" there is a vampire hamster, of all things. It’c called a vampster, and is used to clean cloth that has blood on it. The little critter is pale and wan at first, but after an episode when it cleans the blood from a pair of slacks it’s depicted as hissing, much pinker, and quite frisky.