Disease in Captive Tortoises ---------------------------- Malnutrition and adverse environmental conditions are at the heart of most illness and injury in desert tortoises kept as pets. Like people, tortoises "are what they eat." If improperly fed, they are sure to become ill and remain chronically ill. Tortoises are not well adapted to the increased moisture, dampness and fog so common along the sea coast and in other areas. Pet tortoises are also not well adapted to dealing with automobiles, lawn mowers and marauding dogs. Many illnesses plague desert tortoises. Proper techniques are available to correctly diagnose these conditions, though some diseases may be difficult or impossible to treat.