Bovine Papular Stomatitis

Papular proliferative pathology

Ring Zone Lesions of BPS - Calf (Courtesy of Alun Williams (RVC))

• Parapox virus
• Very similar disease to orf but seen in cattle and generally milder condition.
• Must be differentiated from Foot and Mouth Disease and Mucosal Disease.
• Sporadic, in cattle, less than 1 year old.
• Develop papules on the muzzle, external nares and in the oral cavity; the oesophagus and forestomachs may also be affected.
• Usually heals spontaneously.

Pathogenesis

• The early lesions are round areas of intense congestion up to 1.5 cm in diameter.
• The centre becomes necrotic and slightly depressed.
• Slow peripheral extension of this lesion gives a classical ring zone formation with concentric rings of
  • yellow (necrosis),
  • grey (epithelial hyperplasia)
  • red (congestion).

Histology

• There are focal areas of hydropic degeneration in the stratum spinosum
• Large eosinophilic intracytoplasmic inclusion
• Epidermis is markedly thickened.
• The superficial layers of the epithelium become necrotic and slough.
• Vesicle formation is not a feature of this disease.