Cats have a reputation for being finicky eaters, but that is usually a distortion of the truth. Cats have a very keen sense of taste and smell, and they know what they like. If you have fed your cat the same food for years, then change brands, she may boycott the new menu. If you must change her diet, do it over time, mixing just a bit of the new food with plenty of the old favorite. Slowly increase the amount of new food and decrease the old...