Comparative Analysis of Newcastle Disease Virus Shedding from Naturally Infected Breeds of Poultry in Maiduguri, Nigeria

Abstract

Newcastle Disease (ND) has been considered as a threat to poultry industry worldwide. Despite different strategies aimed at controlling ND in Nigeria, the severe form of the disease continues to occur even in vaccinated poultry farms. The disease is
transmitted primarily through contact with infected or carrier birds. Newcastle disease virus (NDV) shedding through either cloacal or oropharyngeal route play a critical role in the spread of NDV. However, there is paucity of information on the comparative contribution of these routes to NDV shedding. In this study, a total of 256 swab samples were collected from cloacal (n = 128) and oropharyngeal (n = 128) routes from broilers, layers, village chickens, ducks and turkeys that were naturally exposed to NDV. Haemagglutination (HA) and haemagglutination inhibition (HI) tests were carried out to detect the presence of the virus. The results of NDV shedding from cloacal and oropharyngeal routes were compared. The result showed a higher prevalence (42.2%) of NDV shedding from cloacal route when compared with oropharyngeal route (26.6%). In addition, village chickens showed a higher prevalence (43.8%) of NDV shedding when compared with all other breeds sampled. Furthermore, birds at 6 weeks shed higher NDV (66.6%) than the birds of other ages. Therefore, the result of this study showed that the prevalence of NDV shedding was higher in village chickens via cloacal route. There is a need to quantify the amount of NDV shedding in both cloacal and oropharyngeal routes from these breeds of poultry so as to evaluate the viral infective dose.