Vaccination is an essential component to the prevention and control of BVDV infections. Currently, several factors must be considered in the selection and use of vaccines.

• Purpose of vaccination
• Management factors and timing of vaccination
• Risk of disease
• Type and age of animal

Due to the wide ranging, genetic diversity of BVDV, a multivalent vaccine containing at least 2 antigenically different strains is recommended. There is considerable antigenic diversity among BVDV strains, therefore vaccines must provide effective immunity against these diverse strains. Most vaccine manufactures have developed or are developing vaccine containing a type I and type II BVDV strain.

Different vaccination practices and recommendations may be used in different type of animals. Vaccination of weaned calves and feedlot animals is primarily directed at preventing acute infections and associated respiratory tract disease. Vaccination of breeding animals such as cows and replacement heifers is directed at preventing acute infections as well as providing protection of the fetus during gestationa.

In order to break the vicious cycle of persistent infections, is it necessary to prevent exposure of pregnant animals in the first trimester of gestation. Therefore, vaccination of cows and heifers must provide protection also against fetal infection. Vaccines must be efficacious in providing fetal protection against the various BVDV. It is important to remember that vaccination of pregnant animals will not provide complete protection of the fetus. Therefore, it is important to ensure that pregnant animals are not exposed to BVDV especially during the first trimester of gestation.