In a bol, whisk lightly egg whites. Add oatmeal, onion, zucchini, carrots, garlic, Worcestershire sauce, salt, thyme and pepper. Stir. Add ground beef and stir.
On a greased baking sheet with sides, shape the beef mixture in a round loaf of 13 inches of lenght and 2 inches height. Cook in a preheated oven of 350 F for about 40 minutes or until meatloaf is golden. With a spoon, spread salsa on the meatloaf. Keep cooking for about 20 minutes or until the internal temperature is 170°F.