Fig. 1

Clinical signs observed from the outbreak. a A typical torticollis is shown. These symptoms normally occur 7 to 10 days after a complaint of high mortality is reported. b In severely affected birds, mild swollen head and dyspnea with profuse secretions in the trachea were found. c & d Hemorrhagic & necrosis of intestines especially the caecal tonsils & peyer’s patches were found. e Upon PM, the trachea was severely congested and late in the disease stages pericarditis, perihepatitis and caseous air sacculitis were observed. f Proventicular hemorrhages were consistent. g, h & i Bursa atrophy was also commonly found in the outbreak. The cut surfaces of the bursa were hemorrhagic – quite atypical from ND infection which prompted us to look for other infectious agents. Not shown above was atrophic thymus