Animal Science Department


Date of this Version

December 2005


Published for the Proceedings, The Range Beef Cow Symposium XIX December 6, 7 and 8, 2005, Rapid City, South Dakota.


Bovine viral diarrhea virus (BVDV) is a major viral disease impacting beef cattle reproduction and performance. The key source of BVDV infection is the BVDV PI animal. PI animals are the result of fetal exposure to the virus prior to the development of its immune system approximately between day 18 and day 125 of gestation. Exposure to the virus prior to day 18 may result in embryonic death and apparent infertility, while exposure after day 125 is more commonly associated with abortion, stillbirths or congenital abnormalities. BVDV not only lessens reproductive performance but also produces disease in cattle including diarrhea, respiratory insult, mucosal ulcers, and death. The virus suppresses the immune system making the animal more susceptible to infection by other viruses and bacteria therefore those infected with BVDV are less likely to recover. Work to place an economic cost associated with herds infected with BVDV is limited but a US study of the breeding herd indicated a cost of $10.00 to $14.00 per cow while more dramatic results were observed in a study conducted in Great Britain where estimates of €58 ($60) per cow were made. Additional studies within the feedlot have estimated the cost per cwt of gain to be $7.60 or approximately $30 if the animal is expected to gain 400 lbs. during the feeding period. PI calves are more efficient than transiently infected animals in spreading BVDV to other animals. Current initiatives by the National Cattlemen Beef Association (NCBA), American Association of Bovine Practitioners (AABP), the Academy of Veterinary Consultants (AVC), and state livestock associations to develop effective BVDV control programs are underway. Control programs hinge on removal of the PI animal to eliminate the most important source of exposure, effective vaccination programs, and herd level biosecurity.