Pneumomediastinum and subcutaneous emphysema in a rabid bull

This report describes pneumomediastinum and subcutaneous emphysema in a bull with paralytic rabies. The bull displayed severe swelling in the head, neck, chest and forelimbs extending to the ventrum, including the prepuce, 7 days after the development of neurological signs. At necropsy, extensive subcutaneous emphysema was observed in the neck region, abdominal wall and proximal forelimbs. The lungs failed to collapse and had severe emphysema with bullae. Rabies was suspected due to an ongoing outbreak at the farm and was confirmed by histologic lesions and immunohistochemistry. Similar to humans, pneumomediastinum and subcutaneous emphysema should be considered as an unusual complication of rabies in cattle.