Infectious Bronchitis: Infectious bronchitis (IB) is caused by a specific virus known as infectious bronchitis virus (IBV), a member of the Coronavirus genus within the Coronaviridae. Infectious bronchitis is an acute and highly contagious respiratory disease of chickens. It has a worldwide distribution. Several different serotypes of IB virus are known to exist. To control the disease live and inactivated vaccines of various serotypes are in use. Newcastle disease (ND) is an acute viral disease of domestic poultry and many other bird species. Newcastle disease is caused by viruses in the serotype avian paramyxovirus type 1 (APMV-1).