Comparative pathology and immunohistochemistry of Newcastle disease in domestic chicken () and Alabio duck ().

Background: Newcastle disease is very pathogenic in chickens, whereas in ducks, the disease does not show any clinical symptoms.

Aims: To compare the clinical symptoms features, pathological lesions, viral distribution, and apoptosis response caused by the Newcastle disease virus (NDV) in domestic chicken and Alabio duck.

Methods: Forty domestic chickens and 40 Alabio ducks were separated into four groups: domestic chicken and Alabio duck treatment groups, where each was infected by NDV velogenic ducks/Aceh Besar_IND/2013/eoAC080721 in 10ELD dosage. The domestic chicken and Alabio duck control groups were each inoculated with Phosphate Buffer Saline. The infection route was intraorbital, 0.1 ml in volume. Symptoms were observed from day 1 until day 7 post-infection (PI). Necropsy was performed on days 1, 2, 3, 5, and 7 PI for organ collection.

Results: Symptoms observed were disorders in the respiratory, gastrointestinal, and nervous systems, followed by 100% mortality in domestic chickens. In Alabio ducks, there were only depression and slight lethargy. The lesion in domestic chicken day 1 appeared by the lungs, thymus, Fabricius bursa, spleen, and kidney. On day 3 PI, lesions were also found in the heart, proventriculus, duodenum, and cecal tonsil. On days 5 and 7 PI, the trachea and brain lesions were found. In Alabio ducks, lesions were found in the lungs, thymus, spleen, and proventriculus on day 1. Afterward, on day 3, light lesions were found in the heart. On day 5, lesions were found in the trachea and brain; finally, on day 7, light lesions were only found in the thymus, spleen, and brain. Immunopositive reaction NDV in domestic chicken was highest in the proventriculus, duodenum, cecal tonsil, and lymphoreticular organs. In the Alabio duck, it was highest in the duodenum and cecal tonsil. The caspase-3 percentage in domestic chicken increased on day 3 PI; in Alabio ducks, on day 2 PI.

Conclusion: Clinical symptoms and pathological lesions were faster and more severe in domestic chickens. The immunopositive reaction NDV in domestic chicken continued to increase, while in Alabio ducks, it decreased until the last observation day. Apoptosis percentage increased earlier in the Alabio duck than in domestic chicken.