Distribution of bovine virus diarrhoea virus in tissues and white blood cells of cattle during acute infection

This study is performed to gain knowledge about the quantitative distributi on of bovine virus diarrhoea virus (BVDV) in tissues and white blood cells (WBC) at different intervals after acute infection. Ten specific pathogen-f ree calves were intranasally inoculated with 10(5) 50% tissue culture infec tive dose of the non-cytopathic BVDV strain 4800, Twelve hours after inocul ation tonsil biopsies were taken and WBC were collected daily for virus iso lation and titration. Each day one calf was killed and virus isolations and titrations were performed from a range of tissues. The results indicate th at BVDV first replicates in nasal mucosa and to high titers in the tonsil. The virus then appeared to spread to the regional lymph nodes and then diss eminates throughout the body. The virus titers were highest in tonsil, thym us and ileum and were low in the WBC, Also after in vitro infection virus t iters in WBC were very low, whereas, they were high in epithelial cells. Al though the WBC might not be as important as other cells for replication of BVDV, they may play a role in the spread of the virus throughout the body. (C) 1998 Elsevier Science B.V. All rights reserved.