ISOLATION, MOLECULAR DETECTION AND DETERMINIG THE CASE OF VACCINE FAILURE OF NEWCASTLE DISEASE VIRUS OUTBREAKS IN CHICKENS IN WESTERN OROMIA, ETHIOPIA.

Poultry production is an important agricultural activity that provides food, income, and employment opportunities for millions of people in Ethiopia and across the world. Despite its potential, poultry productivity is constrained by infectious diseases, among which Newcastle disease (ND) is one of the most devastating and economically important. ND, caused by Newcastle disease virus (NDV) of the Paramyxoviridae family, leads to high mortality, reduced egg production, and trade restrictions in both backyard and commercial flocks. Although vaccination is widely practiced, ND remains endemic in many parts of Ethiopia, indicating the circulation of virulent NDV strains and potential vaccine failure. . This study will be conducted to isolate, molecularly detect, and determine case of vaccine failure in chickens. A purpossive sampling design will be used, and samples will be collected from both live and dead birds for virus isolation, molecular detection using RT-PCR, and determine case of vaccine failure following WOAH guidelines. The study is expected to provide isolate, molecularly detect and determine case of vaccine failure and supporting improved vaccination, surveillance, and control programs inWestern Oromia, Ethiopia. Keywords: Newcastle disease, NDV, virulence, Western Oromia, poultry, Ethiopia