An orf outbreak in a herd of Boer cross goats

Abstract

A goat herd outbreak of skin lesions characterized by scabby, papillomatous dermatitis on the lips and extending into the buccal cavity was investigated. Initial clinical signs in the first animal affected included acute submandibular edema with swollen mandibular lymph nodes. Necrotic areas were observed on the buccal mucosa. Lesions characteristic of orf developed on the muzzle. Over the next seven days, all but one in the group of 38 doe, doeling and wether goats developed similar lesions. A group of 15 buck kids housed separately was initially unaffected, but two developed mild lesions later. This herd of Boer cross goats had no prior history of orf. Lesions in adult animals were similar in severity and duration to those in the younger animals. Orf virus was found in samples of scab material analyzed using PCR and electron microscopy. All cases resolved spontaneously. Orf is an epitheliotropic parapoxvirus that infects sheep and goats. Virulence factors have been identified through research directed at the immunomodulatory characteristics of the virus. Autogenous or commercial vaccines are available, but are fully virulent virus. Orf is zoonotic to humans, typically causing single target lesions on distal extremities, with rare more serious lymphadenopathies described. Control is directed at strategic vaccination, and limiting infectious material buildup in the environment associated with lambing or kidding.