The Role of Neutrophils in Bovine Ephemeral Fever Virus Infection of Cattle

Abstract

Bovine ephemeral fever is a rhabdoviral disease characterized by a pronounced neutrophilia and an influx of neutrophils into serosae and serosal fluids. Studies were undertaken on the effect of bovine ephemeral fever virus infection of cattle with an induced neutropenia. An equine antiserum to bovine neutrophils was produced using neutrophils derived from a bovine udder. This antiserum was used to deplete circulating neutrophils in three calves that were infected with virulent bovine ephemeral fever virus. The calves became viremic without developing clinical signs and without developing detectable antibodies to bovine ephemeral fever virus. Three months later, after restoration of blood neutrophil levels to normal values, two of these calves were again infected with virulent bovine ephemeral fever virus. Both calves developed viremia, clinical disease, and serum-neutralizing antibodies to bovine ephemeral fever virus.