IBR is an acute, contagious respiratory disease of cattle caused by bovine herpesvirus type 1 (BHV-1), commonly affecting the respiratory tract and the reproductive system. It is highly contagious, resulting in rapid spread of respiratory disease among cattle in close confinement, particularly in feedlots and when groups of cattle are transported.
Bovine Herpesvirus-1 (BHV-1) belongs to the Herpes family of viruses. BHV-1 is highly contagious and can quickly spread through a group of calves. The secretions of affected calves are extremely infectious and appear to be highly attractive to other animals. All ages of animals are potentially at risk. With regard to pneumonia, two other viruses are commonly involved: bovine respiratory syncytial virus and parainfluenza 3 virus.
IBR is a highly contagious and infectious viral disease that affects cattle of all ages. Infection occurs by inhalation and requires contact between animals spreading quickly through the group. The disease is characterised by inflammation of the upper respiratory tract. The virus that causes IBR, Bovine herpes virus 1 (BHV 1) also causes infectious pustular vulvovaginitis in the female, and infectious balanoposthitis in the male and can cause abortions and foetal deformities. IBR is endemic in the UK with around 40% of cattle having been exposed to the virus in the past. Infected cattle develop a latent infection once recovered from the initial infection and despite appearing clinically normal may suffer recrudescence of disease when under stress.
Features of Ibr In Calves
During primary infection, cattle shed virus in high titres in nasal and ocular fluids for approximately 14 days, which can infect in-contact animals. After replication in the lining of the nose, BoHV-1 is transported along nerves and becomes latent in nerve tissue close to where the virus enters, where it remains during the lifetime of the animal. Stress or corticosteroid treatment can lead to the reactivation of BoHV-1, which is then transported back along the nerves to the primary infection site. Shedding of reactivated BoHV-1 may or may not be accompanied by clinical signs of the disease. Each animal once infected with BoHV-1 is a lifelong potential shedder of the virus and poses a risk for its BoHV-1 free herd mates.
Direct transmission occurs through contact with:
- Acutely infected animals
- Latently infected animals in which reactivation of the virus takes place
Indirect transmission may occur through:
- Contaminated semen
- Embryo transfer
- Contaminated materials
- Airborne transmission
Control of the disease is based on the use of vaccines. . Since BHV-1 is a ubiquitous, highly contagious virus, vaccination is recommended as soon as passive immunity in calves has disappeared, usually around four to six months of age. Currently available vaccines for IBR include modified-live-virus (MLV) vaccines and inactivated or killed-virus (KV) vaccines. The timing of vaccination is at least as important as the choice of vaccine. Since maximum protection does not generally occur until approximately three weeks after vaccination, calves should be vaccinated two to three weeks before weaning at which time they start to be at risk of infection.
single vaccination will reduce the severity of disease, but not provide complete protection. The use of marker vaccines is preferred since the antibody they stimulate can be distinguished from the BoHV-1 antibody that follows a natural infection and so secondary vaccination is required.
Prices of Ibr In Calves