In a large bowl, combine the first ten ingredients. Crumble beef over mixture and mix well (mixture will be moist.) Shape into a round loaf; place in a 5-7qt. slow cooker. Cover and cook on low for 5-6 hours or until a meat thermometer reads 160 degrees F.
In a small bowl, whisk the ketchup, brown sugar, mustard and Worcestershire sauce. Spoon over the meat loaf. Cook 15 minutes longer or until heated through. Let stand for 10-15 minutes before cutting.