(Radio Iowa) – Iowans who love Halloween might want to share the holiday with their pets, but if you’re going to put the dog or cat in a costume, one expert says to be sure you’re not stressing them out instead. Megan Matamoros, director of shelter operations at the Animal Rescue League of Iowa, says there are costumes out there for practically every critter, including guinea pigs, but for starters, make sure the costume is a proper fit for your pet. “You want to make sure you get the right size, so there’s everything from extra-extra small to triple extra large,” Matamoros says. “Make sure if you have a golden retriever, for example, that you’re not using a small costume, trying to squeeze them into that costume so that they can breathe appropriately.”

ARL of Iowa photo

Pets have very sensitive hearing, so if you’re putting a hat, hood or anything else on their head, make sure their ears aren’t covered. “And then you don’t want to cover their eyes with a mask with no eye holes, so making sure that they can still see,” she says, “so that they can move around like a normal cat or dog, walking on all four paws, being able to rotate left and right, wag their tail, stick their tongue out and be able to hear. That’s going to be your safest option for your costume.” Some pets simply don’t like to wear costumes, so only dress them up if they don’t become stressed while wearing one. With many animals, she says it’s easy to tell if they’re unhappy in that outfit.

“Sometimes they look like they can’t walk, so if they’re falling over in their costume or constantly digging or tugging at their costume, that may be a sign of uncomfortability,” Matamoros says. “If they’re starting to really pant in their costume heavily, whether that’s a cat or a dog, that can be a sign of stress.”

The A-R-L’s Animal House Store at the Des Moines headquarters has a selection of pet costumes available on sale through Friday.