Tuberculosis is found worldwide, most commonly in small, barnyard flocks and in zoo aviaries; it is rarely found in young flocks. Wild birds, such as cranes, sparrows, starlings, and raptors, have been found to be infected. Tuberculosis has been found in emus and other ratites. The movement of ratites through sales and the long life of these animals have made tuberculosis a major concern for ratite producers. Isolation of ratites purchased at sales is essential to prevent the introduction of tuberculosis into established flocks.