Chronic illness fundamentally alters an animal’s motivational state and coping mechanisms. A cat with chronic cystitis may begin eliminating outside the litter box—not from spite, but from associating the box with pain. Similarly, a horse with gastric ulcers may develop crib-biting as a coping strategy to increase salivary buffering of gastric acid. In these cases, treating the primary medical condition without addressing the learned behavioral component often leads to treatment failure.