article · Animals
Newcastle disease virus causes severe economic damage to poultry production globally and experiences frequent outbreaks in Egypt. An investigation of wild cattle egrets and house sparrows collected near chicken farms in Kafrelsheikh Governorate confirmed the presence of velogenic Newcastle disease virus sub-genotype VII.1.1. Molecular testing detected the virus in 44 percent of egrets and 26 percent of sparrows using real-time polymerase chain reaction assays. The identified viral strains showed high genetic similarity, reaching up to 99.7 percent identity, with previously catalogued Egyptian strains. When inoculated into susceptible specific-pathogen-free chickens, the wild bird isolates produced severe clinical disease, marked tissue damage in the lungs, spleen, and brain, and caused mortality rates between 67.5 and 70 percent. These results demonstrate that common wild birds harbour virulent viral strains capable of inducing fatal disease in domestic poultry.
Newcastle disease poses a continuous threat to global poultry production and rural livelihoods by causing devastating flock losses. Demonstrating that common wild birds near farms carry highly lethal viral strains clarifies how outbreaks may be initiated and maintained. This knowledge assists poultry producers, veterinarians, and biosecurity managers in recognising external infection routes and designing stricter farm measures to prevent wild bird contact.
This early-stage epidemiological research provides surveillance data that could inform diagnostic test developers, vaccine manufacturers, and poultry biosecurity consultants. Veterinary health authorities and farm operators can use the genetic and pathology findings to update risk assessments, biocontainment protocols, and monitoring programmes. Real-world application is at an early stage, as commercial translation requires broader surveys of other wild bird species and comparative studies with circulating domestic poultry strains.
AI-generated from the published abstract. Always read the original work before citing.
Newcastle disease (ND) is considered to be one of the most economically significant avian viral diseases. It has a worldwide distribution and a continuous diversity of genotypes. Despite its limited zoonotic potential, Newcastle disease virus (NDV) outbreaks in Egypt occur frequently and result in serious economic losses in the poultry industry. In this study, we investigated and characterized NDV in wild cattle egrets and house sparrows. Fifty cattle egrets and fifty house sparrows were collected from the vicinity of chicken farms in Kafrelsheikh Governorate, Egypt, which has a history of NDV infection. Lung, spleen, and brain tissue samples were pooled from each bird and screened for NDV by real-time reverse transcriptase polymerase chain reaction (RRT-PCR) and reverse transcriptase polymerase chain reaction (RT-PCR) to amplify the 370 bp NDV F gene fragment. NDV was detected by RRT-PCR in 22 of 50 (44%) cattle egrets and 13 of 50 (26%) house sparrows, while the conventional RT-PCR detected NDV in 18 of 50 (36%) cattle egrets and 10 of 50 (20%) of house sparrows. Phylogenic analysis revealed that the NDV strains identified in the present study are closely related to other Egyptian class II, sub-genotype VII.1.1 NDV strains from GenBank, having 99.7-98.5% identity. The pathogenicity of the wild-bird-origin NDV sub-genotype VII.1.1 NDV strains were assessed by experimental inoculation of identified strains (KFS-Motobas-2, KFS-Elhamoul-1, and KFS-Elhamoul-3) in 28-day-old specific-pathogen-free (SPF) Cobb chickens. The clinical signs and post-mortem changes of velogenic NDV genotype VII (GVII) were observed in inoculated chickens 3 to 7 days post-inoculation, with 67.5-70% mortality rates. NDV was detected in all NDV-inoculated chickens by RRT-PCR and RT-PCR at 3, 7, and 10 days post-inoculation. The histopathological findings of the experimentally infected chickens showed marked pulmonary congestion and pneumonia associated with complete bronchial stenosis. The spleen showed histocytic cell proliferation with marked lymphoid depletion, while the brain had malacia and diffuse gliosis. These findings provide interesting data about the characterization of NDV in wild birds from Egypt and add to our understanding of their possible role in the transmission dynamics of the disease in Egypt. Further research is needed to explore the role of other species of wild birds in the epidemiology of this disease and to compare the strains circulating in wild birds with those found in poultry.
This page summarises published work. The authoritative version sits with the publisher.
DOI: 10.3390/ani11020505
Is something wrong with this record? Report it or request removal.
Discussion
Have you built on this work, tried to replicate it, or seen it applied in practice? Share what you know. Verified researchers and MARATTO™ domain experts can open a discussion, and any member can reply. Contributions are reviewed before they appear.
No discussion yet. Open the first thread.
New to MARATTO™? Create a free account.
