Experimental Infection of Japanese Quails (Coturnix coturnix japonica) with Avian Orthoavula Virus-1: Pathogenicity and Transmissibility of Velogenic Genotype VII.1.1

Abdelaal, Khaled; Mansour, Shimaa; Ismaiel, Mohamed; Ali, Ahmed

doi:10.21608/ejvs.2025.334876.2490

Experimental Infection of Japanese Quails (Coturnix coturnix japonica) with Avian Orthoavula Virus-1: Pathogenicity and Transmissibility of Velogenic Genotype VII.1.1

Articles in Press

Document Type : Original Article

Authors

¹ Department of Virology, Faculty of Veterinary Medicine, Zagazig University, Zagazig, Egypt

² Department of Virology, Faculty of Veterinary Medicine, Zagazig University

³ Department of Virology, Faculty of Veterinary Medicine, Zagazig University, Zagazig, Egypt.

10.21608/ejvs.2025.334876.2490

Abstract

Avian orthoavulaviruses1, formerly known as Newcastle disease virus (NDV) is able to infect a wide variety of bird species resulting in various clinical signs and consequences. The easiness of transmission has endorsed the virus to spread globally showing variable levels of virulence based on host species and virus strain. The pathogenicity and transmissibility of field Egyptian chicken-origin NDV genotype VII 1.1 to induce the disease in 35-day-old Japanese quails were investigated. Twenty-five percent of quails inoculated oculonasally with 10⁶EID₅₀ showed conjunctivitis and depression, whereas 11% of cases exhibited greenish diarrhea. Neurologic signs consisting of incoordination and tremors were recorded in 37.5% of infected quails at day 8 post-infection (dpi). Congested meningeal blood vessels and hemorrhagic cecal tonsils were seen in both NDV-infected and contact quails. Microscopically, the NDV-infected quails showed brain edema, lymphocytic encephalitis and pulmonary congestion. Using hemagglutination inhibition (HI) assay, the anti-NDV antibodies for NDV-infected and LaSota-vaccinated at 7 dpi were relatively similar. The antibody titers reached 6±0.8 log₂ in the NDV-infected birds and 5.25±0.5 and 4±0.8 log₂ in LaSota-vaccinated and contact quails, respectively at 21 dpi. Additionally, the infected quails shed virus via the oropharynx and cloaca. Virus titers of approximately 10^2.8 and 10^5.2EID₅₀/mL were determined in the oropharyngeal and cloacal swabs on day 5 post-infection, respectively. These results demonstrate that Japanese quails can indeed be susceptible to NDV genotype VII 1.1 and might be a source of infection to additional birds.

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