Investigation of Newcastle Disease Virus Infection in Pet Birds in the Southwest of Iran.

Newcastle disease virus (NDV) is a serious threat to the international poultry industry. Therefore, to determine the role of pet birds (Psittaciformes and Passeriformes) in its spread and epidemiology, the presence of this virus in these birds was investigated. In this study, fecal and cloaca swabs from 63 Psittaciformes and 37 Passeriformes, along with tissue samples of dead birds, including proventriculus, trachea, lungs, and intestine, were collected from breeding and sales markets as well as the birds referred to Faculty of Veterinary Medicine, Shahid Chamran University of Ahvaz, Ahvaz, Iran. Isolation of the virus was performed by injecting the suspension of the samples into the allantoic fluid of fertilized eggs, and NDV was detected in the achieved allantoic fluids by reverse transcription polymerase chain reaction. The NDV was detected in 13 allantoic samples. The partial F gene sequences of 10 positive samples were investigated, and their genetic relationship with each other as well as with other isolates in the gene bank was marked. Consequently, subgenotype VII.1.1 (VIId) was in the locus of all 10 viruses. By the amino acid cleavage site sequences of F protein, 10 isolates were determined as velogenic NDV. Moreover, all sequences were similar to each other and other Iranian isolates. Furthermore, the 112RRQKR/F117 pattern was the main amino acid (aa) sequence in the F-protein Cleavage site for VIId genotype isolates.