Gross lesions were similar in severity between sheep and goats. Antibody response to the infection was also similar. Mastitis-causing bacteria were isolated from milk samples of all the infected sheep and goats, but not from the controls. The mean course of the disease ranged between 25 to 33 days and averaged 29.2 days.
Researchers concluded that udder orf lesions have a direct contribution to increasing the rate of clinical and sub-clinical mastitis among infected ewes and goats; orf disease poses a serious problem to lambs and kids, preventing them from suckling and thus causing starvation; and mastitic orf lesions can become complicated, leading to amputation of the udder in severe cases or death of the affected animals.
Source: Veterinarski arhiV 78 (3), 217-225, 2008