Is plain, skinless cooked duck meat a good occasional protein for my cat?

Yes, plain cooked duck meat, especially the breast without skin, is safe to share with your cat as an occasional treat. It's a good source of protein, but it is also a rich meat, so it's important to remove all skin and visible fat to avoid stomach upset. Offer only a small, bite-sized amount that's fully cooked and free of any seasoning, bones, or sauces. Most cats enjoy it, but introduce it slowly and watch for any digestive changes, stopping if it doesn't agree with them.