Clinical, Pathological and Serological Identification of Newcastle Disease in Chicken in Kintamani and Susut District of Bangli, Bali

Abstract

Newcastle Disease (ND), caused by Avian Paramyxovirus serotype 1 (APMV-1), remains endemic in Indonesia and continues to threaten poultry production due to its high transmissibility and economic impact. This study aimed to identify ND through an integrated clinical, pathological, and serological approach in commercial and indigenous chickens from Susut and Kintamani Districts, Bangli Regency, Bali. A total of 32 clinically suspected chickens (16 per district) were examined by necropsy, virus isolation in embryonated chicken eggs, and confirmation using hemagglutination (HA) and hemagglutination inhibition (HI) tests. Fifteen samples (46.88%) were confirmed ND-positive, comprising 7 (43.75%) from Susut and 8 (50%) from Kintamani. Digestive disorders were the predominant clinical sign (86.66%), and characteristic lesions were most consistently observed in the lungs (100%), intestines, and cecal tonsils (93.33%). Chickens from Kintamani had a 1.29-fold higher risk of ND infection compared to Susut (OR 1.29; 95% CI: 0.3–5.4). The study demonstrates active ND circulation in Bangli Regency and reveals variability in clinical expression potentially influenced by management systems and biosecurity practices. By integrating field-based clinical assessment with pathological and HA/HI confirmation, this research strengthens practical diagnostic reliability in resourcelimited settings and provides region-specific epidemiological evidence to support targeted vaccination strategies, enhanced biosecurity implementation, and sustainable poultry health management in endemic areas.