History: Defassa waterbuck, 14 years, female
Diagnosis: Palate: stomatitis, severe, multifocal to confluent, chronic, ulcerative, suppurative and necrotizing
Agent: Trueperella pyogenes and Fusobacterium species
Description: Macroscopically, the waterbuck had severe ulcerations in the oral cavity with a focus on the palate as well as in the mucosa of the cheek, of up to 21.8 x 3.0 x 1.5 cm in dimension. The tongue was unaffected. In addition, a severe, multifocal, chronic, suppurative myositis was found in the cheek.
Comment: Five Defassa waterbucks lived together in a zoo compound. They had been anorexic and had halitosis over a period of 8 days. All animals showed the same macroscopic lesions of stomatitis. Within the rumen, mucosal ulcerations were found mostly on or near the rumen pillars, partly chronic, partly subacute, with variable hemorrhagic margins. Severe mucosal and submucosal necroses, with marked neutrophil infiltrations were found in tissue sections stained with HE. Gram positive as well as gram negativ short rods were located at the border to healthy tissue in Gram-stains. Bacterial culturing identified Trueperella pyogenes and Fusobacterium speciesin samples of the palatum and rumen. The animals had been fed black locust (Robinia pseudoacacia) with thorny plant parts before onset of the lesions.
Picture & Authored by: Stefanie Binder, Department of Veterinary Pathology, Freie Universität Berlin, Germany