Preheat oven to 350. Position a rack in the middle of the oven. In a small bowl, combine milk and dressing mix; let stand for five minutes. In a mixing bowl, combine chicken, milk mixture, bread crumbs, eggs, and black pepper. Mix well. Transfer meat mixture to a 9" x 5" loaf pan, mounding it slightly; smooth the top of the loaf with the back of a spoon. Spread the ketchup evenly over the loaf. Bake meat loaf for 1 1/2 hours, or until an instant-reading thermometer inserted into the center of the loaf registers 185 degrees. Let the loaf rest on a rack for ten minutes before slicing.