Newcastle Disease Virus Infection in Quail

Abstract

Newcastle disease (ND), caused by virulent strains of Newcastle disease virus (NDV), is a devastating disease of poultry worldwide. The pathogenesis of ND in quail is poorly documented. To characterize the ability of virulent NDV strains to replicate and cause disease in quail, groups of 14 two-week-old Japanese quail ( Coturnix japonica) were experimentally inoculated with 10 EID (embryo infectious dose 50%) units of 1 of 4 virulent NDV strains: 2 isolated from quail ( N2, N23) and 2 from chickens ( Israel, Pakistan). At day 2 postinfection, noninfected quail (contact group) were added to each infection group to assess the efficacy of virus transmission. Tested NDV strains showed moderate pathogenicity, with highest mortality being 28% for the N2 strain and below 10% for the others. Two N2-inoculated birds showed neurological signs, such as head tremor and ataxia. Microscopic lesions were present in N2-, Israel-, and Pakistan-inoculated birds and consisted of nonsuppurative encephalitis. Contact birds showed no clinical signs or lesions. In both inoculated and contact birds, virus replication was moderate to minimal, respectively, as observed by immunohistochemistry in tissues and virus isolation from oropharyngeal and cloacal swabs. Strains originally isolated from quail resulted in higher numbers of birds shedding in the inoculation group; however, transmission appeared slightly more efficient with chicken-derived isolates. This study shows that virulent NDV strains have limited replicative potential and mild to moderate disease-inducing ability in Japanese quail.

Pathogenesis of Different Genotypes of Egyptian Virulent Newcastle Disease Virus (NDV) Previously Isolated from Chickens in Japanese Quails (Coturnix coturnix japonica)

“…These clinical signs were progressed in intensity at 7 dpi and involved more quails. The neurological clinical signs as a result of tropism of virulent NDV strains to the nervous tissues were also previously reported (Ecco et al, 2011;Susta et al, 2018). Our results showed that the quails inoculated by NDV VIId failed to develop a severe systemic infection in comparison to NDV VIb, although using the same dose (10 7 EID 50 /quail) as well as the same route (oculo-nasal route).…”

Diagnostic and Vaccination Approaches for Newcastle Disease Virus in Poultry: The Current and Emerging Perspectives

“…Backyard chicken, geese, and ducks which are naturally less susceptible to virulent NDV are also incriminated in maintaining the virus in the environment [ 50 ]. Furthermore, exotic pet birds kept in close proximity to commercial poultry have been shown to harbour virulent NDV strains that are genetically highly related to those obtained in the commercial farms [ 51 ]. This occurrence of virulent NDV in apparently healthy wild and backyard poultry not only constitutes a huge diagnostic challenge but also represents a big biosecurity threat to the commercial poultry industry.…”

Transboundary Animal Diseases, an Overview of 17 Diseases with Potential for Global Spread and Serious Consequences

“…Most of the research into NDV is done as viral challenge models in chickens or in ovo using SPF embryonated chicken eggs, but the strain of chicken and the precise definition of SPF are not often disclosed [444,[478][479][480][481][482][483]. The most commonly reported strain of chicken used is the White Leghorn, along with others such as White Rock and Isa Brown layers [120,447,[484][485][486]. It is known that differences in the innate immune response in differing breeds of chicken can have drastic effects on the response to infection [487], making this important in describing the model.…”