- Disease of cattles and ruminants caused by pestivirus - There are 4 major species BVDV-1, BDVD-2 , Border Disease Virus of sheep and classical swine fever virus, previously known as hog cholera virus.
- Persistently Infected (PI) animals. Causes repiratory, reproductive problems
- BVD is brought into herds such as this via persistently infected animals that were congenitally infected with BVD virus. These animals shed virus and infect herd mates. Thus it is necessary to check all purchased animals to be sure they are BVD free.
- Following is the most likely to achieve the goal of maintaining a BVD free herd in the future. Before purchase, test all heifer replacements for BVD virus using immunohistochemistry on a skin biopsy
- It would also be wise to also vaccinate all cattle on this dairy with killed BVD vaccine just to ensure that if BVD did appear, it would be less likely to cause a major problem. Initial vaccination requires two injections, followed by a yearly booster. Vaccination alone however, will not keep the herd BVD free if a BVD carrier heifer is brought in.
Diagnosis and differentials
Respiratory Viruses
- When cattle are diagnosed with pneumonia, BVDV is found frequently along with other bacteria and viruses. These infections are referred to as coinfections. Some of the other bacteria and viruses are bovine herpesvirus-1, parainfluenza-3 virus, bovine respiratory coronavirus, bovine respiratory syncytial virus, Pasteurella, Mycoplasma, and Hemophilus. BVDV may increase the severity of these infections because BVDV causes immunosuppression in infected animals. In other situations, BVDV may increase the virulence of the pathogens.