Infectious Bursal Disease (IBD) is a viral infection that primarily affects young chickens, particularly those between three and six weeks old. The disease is caused by the Infectious Bursal Disease Virus (IBDV), which targets the bursa of Fabricius, an important organ for the immune system in birds. Infected chickens may show symptoms such as depression, diarrhea, and a decrease in egg production. The disease is highly contagious and can spread through direct contact with infected birds or contaminated environments. Vaccination is a common preventive measure, helping to protect flocks from severe outbreaks. Effective biosecurity practices are also essential to control the spread of IBD.