Diagnosis of Newcastle disease in broiler by histopathology and immunohistochemistry

Newcastle disease (ND) is an OIE notifiable, highly contagious, generalized viral disease of poultry. It remains a constant threat to the poultry industry and is a limiting disease for poultry producers worldwide. The present study report a severe enteric form of ND virus infections in backyard poultry birds by using histopathology and immunohistochemistry. ND viral antigens were detected in the lesions of various organs. ND viral antigen were mainly localized in the cytoplasm and nuclei of necrotic cells of epithelium of proventriculus, gizzard and intestines, Kupffer cells and circulating monocytes in the liver, tracheal epithelial cells, bronchiolar and parabronchiolar epithelial cells and alveolar macrophages in the lungs. Thus, immunohistochemistry serve as rapid and reliable tools to study the tropism and distribution of ND viral antigen in the tissues of infected birds and hence its diagnosis.