Foods to avoid
You want to avoid grapes, tomatoes and the core of apples, pears etc... The seeds are toxic. Grapes can cause kidney failure. I have read horror stories of how people lost their pets because of feeding grapes. Onions and garlic are also to be avoided. No corn or cobs of corn.
I give carrots, bananas, pieces of apple (no core) pieces of broccoli, celery, pieces of lettuce etc... All in moderation.