A sheep presents with crusty papules on its lip. What should the veterinarian do?

The presence of crusty papules on a sheep's lip can suggest a condition that may have zoonotic potential, such as contagious ecthyma or orf, which is caused by a poxvirus. Given the nature of these types of lesions and the risk of transmission to humans, it is crucial for the veterinarian to inform the owner of the zoonotic potential. This step is essential in ensuring that the owner takes appropriate precautions to protect themselves and others, especially if the sheep has been in contact with children or immunocompromised individuals who may be more susceptible to infection.

While other actions like isolating the sheep, conducting a blood test, or prescribing treatment can be part of the overall management plan, they do not address the immediate need for awareness and prevention of potential zoonotic transmission. The emphasis on informing the owner highlights the importance of public health considerations in veterinary practice.