While dogs often have appetites and nutritional needs similar to their human companions—and will usually eat whatever you offer them—other animals have more specific needs. Cats are “obligate carnivores,” says Dr. Weitzman, meaning it’s a biological necessity for them to eat meat, and therefore they require more protein than other pets.

Here’s what to feed other small pets:

Birds

Pet birds should eat only very small amounts of fattening seed, because they contain little nutritional value. Instead, they should be fed high-quality, organic pellet and a variety of fresh fruits, vegetables, and grains.

Rabbits

As with birds, limit the amount of non-nutritious foods and opt for a high-fiber, low-protein diet, abundant water, and added fresh vegetables and fruit. A good rule of thumb is to feed one cup of greens—such as kale, alfalfa, bok choy, parsley, and radish tops—per four pounds of body weight. Fruit should be limited to two small pieces per week.

Hamsters

High-energy hamsters have fast metabolisms and require only a tablespoon of pellets per day, supplemented by fresh treats like greens or fruit. Also, because they tend to hoard or stash their food, don’t feel you always need to refill an empty bowl.

Reptiles

The popular pet iguana should be fed a variety of dark leafy green vegetables, supplemented by a small amount of fruits and flowers.