肠球菌性脊柱炎，脊柱炎症，鸡

A. Infection by pathogenic Enterococcus cecorum is observed grossly as bulbous enlargement of the free thoracic vertebra (arrows). B. A longitudinal section of the vertebral column reveals tan to white, caseous exudate within the free thoracic vertebra (black arrow) and compressing the overlying spinal cord (white arrows).