Lack of antibodies to porcine circovirus type 2 virus in beef and dairy cattle and horses in western Canada.

Porcine circovirus type 2 (PCV2) is a recently recognized agent that is consistently associated with postweaning multisystemic wasting disease in swine. There are conflicting data concerning the ability of this virus to infect and cause disease in other species. To determine if normal cattle, cattle affected with various illnesses, and normal horses in endemic areas of PCV2 infection in swine have had PCV2 infections, 100 randomly selected bovine sera, 100 equine sera, and 100 colostrum samples from clinically normal dairy cattle were examined for the presence of antibodies to porcine circoviruses by using ELISAs. All samples tested were negative for antibodies to porcine circoviruses. As well, a seronegative neonatal Holstein calf and 6 seronegative, 6-month-old beef calves that were experimentally infected with PCV2 failed to develop antibodies to the virus. These results suggest that natural infection of cattle and horses with PCV2 does not occur, or is a rare event, in western Canada.