National Veterinary Laboratory, Bulowsvej 27, P.O. Box 373, DK-1503 Copenhagen, Denmark
A survey of all cattle in 19 Danish dairy herds with unknown status of bovine virus diarrhoea virus (BVDV) infection showed that 1.4% of the animals were persistently infected with BVDV.
Persistently infected animals were detected in ten herds (53%), in numbers varying from one to ten animals per herd. The prevalence of neutralizing antibody-seropositive animals in herds with one or more persistently infected animals was 87%, whereas the prevalence in herds without persistently infected animals was 43%. Seropositive animals were found in all herds.
There was a logarithmic relationship between age and prevalence of seropositive animals. The the-oretical risk of fetal infections occurring during the first 3 months of pregnancy was estimated to be 3.3%, close to the observed prevalence (2.9%) of persistently infected animals less than 1 year of age.
This article was published in Preventive Veterinary Medicine, 11, H. Houe and A. Meyling, Prevalence of bovine virus diarrhoea (BVD) in 19 Danish dairy herds and estimation of incidence of infection in early pregnancy, 9-16, Copyright Elsevier 1991.