Newcastle Disease Virus Shedding Among Healthy Commercial Chickens and its Epidemiological Importance

Newcastle disease virus (NDV), shedding among apparently healthy commercial chickens reared intensively in Nsukka and its environs were studied. Samples were collected from birds that were not vaccinated against Newcastle disease (ND), and also from those that were vaccinated but given an interval of 28 days between vaccination and sample collection. Cloacal and tracheal swabs were collected from each bird and a total of 1800 birds were sampled from 72 farms located in the area. The birds in the area were monitored for 15 days post sampling. The samples were examined for NDV by isolation in embryonated chicken eggs through the allantoic cavity route. Result showed an isolation frequency of 3.2% and this could be termed as the prevalence of NDV in clinically healthy chickens in Nsukka area as the birds remained apparently healthy for more than 15 days. We therefore conclude that there is virus shedding among healthy commercial chickens in Nsukka and its environs and this should be considered an important epidemiological factor in the spread of the disease. Healthy carriers can serve as short term reservoirs and transmit the disease to other birds.