Abstract:
The article includes the dynamic histological modification in bursa of Fabricius in chickens the age 4-5 weeks. It describes the structural modification in dependence of period after contamination and in chicken after disease. In severe cases of infectious bursal disease all the follicules are affected simultaneously. Factors that determine the severity of infection include virulence of infectious bursal disease virus, concentration of virus, level of imunity and management factors.
