Infectious bursal disease

Infectious bursal disease of chickens ( IBu, Gumboro disease, Infectious Bursal Disease, Avian nephrosis ) is a disease liable occurring viral disease of young chickens, which is accompanied by a hemorrhagic inflammation of the bursa of Fabricius. It was first observed in 1957 in Gumboro, Delaware (USA) and is now represented worldwide. It belongs to the notifiable animal diseases.

Pathogens and occurrence

The causative agent of infectious bursal disease Infectious bursal disease virus is the virus (IBDV ) from the family Birnaviridae. There are two different serotypes and 17 different virus strains.

The virus mainly affects chickens, but also turkeys, ducks may also be susceptible. A cultivation of the virus can be carried out in embryonated chicken eggs, chicken fibroblast cultures or embryonic bursal cells.

The disease occurs worldwide. The virus is excreted in the feces. The virus is extremely resistant to environmental influences. Add chicken coops can stay up to 52 days up to 122 days infectious in animal feed. Infection occurs mainly via indirect contact with virus- contaminated objects.

Clinical picture

The disease is characterized by a characteristic of the disease. It only ill juveniles up to the age of 11 weeks. After an incubation period of 2 to 3 days it comes in almost all animals ( morbidity up to 100% ) to restlessness, decreased feed intake, ruffled feathers, diarrhea grünweißlichem, dehydration and tremors. By the 3rd day after the onset, there is a sharp increase in deaths from 5 / 6 Decrease significantly day again. The mortality rate is up to 30%. Chronically infected animals show reduced weight gain and anemia.

With renewed outbreaks in the same herd, the disease is very mild, possibly even unnoticed.

Diagnostics and control

Pathologically show enlargement, edema, and yellowing of the bursa of Fabricius, a severe intestinal inflammation and muscle bleeding. This is already characteristic together with the clinical course. A cultivation of the virus can occur in the above-described cell cultures.

A causal therapy is not possible. Also disinfection measures can not stop the spread of the high tenacity of the virus as a rule. The most effective control measure is vaccination of dams. It is carried out 3-7 weeks before the onset of lay, and then refreshed annually. Vaccination protects newly hatched chicks by transmitted via the egg antibodies.