Aidin Molouki1, Mohammad Hossein Fallah Mehrabadi1, Mohsen Bashashati2, Mohsen Mahmoudzadeh Akhijahani1, Swee Hua Erin Lim3,4, Saeed Amir Hajloo5. 1. Department of Avian Disease Research and Diagnostic, Razi Vaccine and Serum Research Institute, Agricultural Research Education and Extension Organization (AREEO), Karaj, Iran. 2. Department of Avian Disease Research and Diagnostic, Razi Vaccine and Serum Research Institute, Agricultural Research Education and Extension Organization (AREEO), Karaj, Iran. m.bashashati@rvsri.ac.ir. 3. Health Sciences Division, Abu Dhabi Women's College, Higher Colleges of Technology, 41012, Abu Dhabi, United Arab Emirates. 4. Centre for Research Excellence and School of Data Science, Perdana University, Block D, MAEPS Building, 43400, Serdang, Selangor, Malaysia. 5. Department of Health and Management of Poultry Disease, Iranian Veterinary Organization (IVO), Tehran, Iran.
Abstract
BACKGROUND: Based on our previous work, it was discovered that some Newcastle disease virus (NDV) isolates from backyard poultry between 2011 and 2013 in Iran formed a new separate cluster when phylogenetic analysis based on the complete F gene sequence was carried out. The novel cluster was designated subgenotype VII(L) and published. AIM: In the current study, for further validation, we initiated a comprehensive epidemiological study to identify the dominant NDV genotype(s) circulating within the country. Collection of samples was executed between October 2017 and February 2018 from 108 commercial broiler farms which reported clinical signs of respiratory disease in their broilers. RESULT: We report that 38 of the farms (> 35%) tested positive for NDV. The complete F gene sequences of seven of the isolates are shown as representative sequences in this study. According to the phylogenetic tree constructed, the recent broiler farm isolates clustered into the newly designated cluster VII(L) together with the older Iranian backyard poultry isolates in our previous work. All the sequences shared the same virulence-associated F cleavage site of 112RRQKR↓F117. CONCLUSION: Our phylogenetic analysis suggested that the NDV subgenotype VII(L) may have been derived from subgenotype VIId, and contrary to popular belief, subgenotype VIId may not be the dominant subgenotype in Iran. Tracking of the subgenotype on BLAST suggested that the NDV subgenotype VII(L), although previously unidentified, may have been circulating in this region as an endemic virus for at least a decade. Other NDV genotypes, however, have also been reported in Iran in recent years. Hence, ongoing study is aimed at determining the exact dominant NDV genotypes and subgenotypes in the country. This will be crucial in effective mitigation of outbreaks in Iranian broiler farms.
BACKGROUND: Based on our previous work, it was discovered that some Newcastle disease virus (NDV) isolates from backyard poultry between 2011 and 2013 in Iran formed a new separate cluster when phylogenetic analysis based on the complete F gene sequence was carried out. The novel cluster was designated subgenotype VII(L) and published. AIM: In the current study, for further validation, we initiated a comprehensive epidemiological study to identify the dominant NDV genotype(s) circulating within the country. Collection of samples was executed between October 2017 and February 2018 from 108 commercial broiler farms which reported clinical signs of respiratory disease in their broilers. RESULT: We report that 38 of the farms (> 35%) tested positive for NDV. The complete F gene sequences of seven of the isolates are shown as representative sequences in this study. According to the phylogenetic tree constructed, the recent broiler farm isolates clustered into the newly designated cluster VII(L) together with the older Iranian backyard poultry isolates in our previous work. All the sequences shared the same virulence-associated F cleavage site of 112RRQKR↓F117. CONCLUSION: Our phylogenetic analysis suggested that the NDV subgenotype VII(L) may have been derived from subgenotype VIId, and contrary to popular belief, subgenotype VIId may not be the dominant subgenotype in Iran. Tracking of the subgenotype on BLAST suggested that the NDV subgenotype VII(L), although previously unidentified, may have been circulating in this region as an endemic virus for at least a decade. Other NDV genotypes, however, have also been reported in Iran in recent years. Hence, ongoing study is aimed at determining the exact dominant NDV genotypes and subgenotypes in the country. This will be crucial in effective mitigation of outbreaks in Iranian broiler farms.
Authors: Diego G Diel; Luciana H A da Silva; Hualei Liu; Zhiliang Wang; Patti J Miller; Claudio L Afonso Journal: Infect Genet Evol Date: 2012-08-07 Impact factor: 3.342
Authors: Hatem S Abd El-Hamid; Manal E Shafi; Najah M Albaqami; Hany F Ellakany; Naglaa M Abdelaziz; Mohamed N Abdelaziz; Mohamed E Abd El-Hack; Ayman E Taha; Khalid M Alanazi; Ahmed R Elbestawy Journal: BMC Vet Res Date: 2020-07-22 Impact factor: 2.741