Sarcoids in captive zebras (Equus burchellii): association with bovine papillomavirus type 1 infection.

The research article investigates a case of sarcoids in two captive zebras infected with bovine papillomavirus type 1, highlighting the similarities with previously documented cases in horses. The lesions were histologically similar to equine cutaneous neoplasm, commonly known as “sarcoid”.

Study methodology and findings

• The study was conducted on two zebras, in different captive facilities, diagnosed with sarcoids. Zebra 1, a 4.5 years old male, had an inguinal mass which reoccurred even after surgical excision and treatment. Zebra 2 had a single ulcerated mass on the nose which was cured through surgical excision.
• Upon histological examination, the masses in both zebras showed similar characteristics to the equine cutaneous neoplasm, commonly referred to as a “sarcoid”. These characteristics included a dermal, compact, non-encapsulated, poorly demarcated neoplasm composed of well-differentiated spindle cells accompanied by moderate epidermal hyperplasia.
• The researchers used polymerase chain reaction, nucleic acid sequencing, and in situ hybridisation (ISH) on paraffin-embedded tissues from the inguinal mass of zebra 1 to demonstrate association with bovine papillomavirus (BPV) type 1.
• The nucleic acid sequencing revealed a 98% identity of the 244-bp fragment with BPV type 1 and the ISH for BPV type 1 DNA intensely stained the nuclei of neoplastic mesenchymal spindle cells, further confirming the diagnosis.

Significance of the findings

• This is the first descriptive study on sarcoids in captive zebras, identifying the association with BPV type 1. The lesions presented in zebras are similar to those found in horses affected by the same virus, despite the different species.
• The findings suggest that zebra and horse sarcoids, despite occurring in different species, might have similar causes. This has potential implications for disease management, treatment, and prevention strategies in both horses and zebras.
• The study offers new insights into the pathogenic role of BPV type 1, enhancing the scientific understanding of the virus’ host range, its mechanisms of oncogenesis, and potential for transmission between different animal species.