Detection and molecular characterization of enteric viruses in enteritis-affected commercial broiler chickens in India

Abstract

Summary. -A study was conducted to detect and characterize the enteric viruses (chicken astrovirus, avian nephritis virus and avian orthoreovirus) present in flocks of commercial broiler chickens suffering from enteritis in Haryana, India. The intestinal contents were collected from 65 enteritis-affected flocks (cases) and tested by reverse transcription PCR (RT-PCR). Of these 65 cases, 35 (53.80%) were positive for a single virus and 26 (40.00%) for two viruses. The remaining four samples were negative for all three viruses tested. Of the 65 cases, 57 were positive for chicken astrovirus (CAstV) while 30 cases had avian nephritis virus (ANV). None of the cases were positive for orthoreovirus. Comparison of 12 CAstVs of this study with previously published CAstV sequences revealed nucleotide identities ranging from 73.20 to 98.00%. The nucleotide identities ranged between 83.10-95.50% when nine ANVs of this study were compared with previously reported ANV sequences. The amino acid sequences of CAstVs in comparison to previously published sequences revealed certain unique changes. Phylogeny based on polymerase gene revealed that CAstVs and ANVs of this study were under the same monophyletic clade. In conclusion, a large number of broiler chicken flocks experiencing enteritis were positive for CAstV and ANV by RT-PCR. The presence of more than one enteric virus in enteritis-affected flocks and changes at the genetic level in these viruses may affect the severity of disease.Keywords: chicken astrovirus; avian nephritis virus; avian orthoreovirus; broiler chicken; India * Corresponding author. E-mail: nareshjindal1@gmail.com; phone: +91-1662-289323. Abbreviations: ANV = avian nephritis virus; ARV = avian reovirus; CAstV = chicken astrovirus; GI = gastrointestinal; PES = poult enteritis syndrome; RSS = runting and stunting syndrome; RT-PCR = reverse transcription PCR

Characterization and genomic analysis of emerging astroviruses causing fatal gout in goslings

“…ORF1a encodes non‐structural proteins, ORF1b encodes RNA‐dependent RNA polymerase, and ORF2 encodes nucleocapsid proteins. Avastrovirus (AAstV) isolated from avian species (Bulbule et al, ; Fu et al, ; Kaithal, Jindal, Kumar, & Mor, ; Mándoki, Dobos‐Kovács, Bakonyi, & Rusvai, ; Ter Veen, de Bruijn, Dijkman, & de Wit, ) is one of the leading causes of diseases in birds such as nephritis in chickens, hepatitis and stunting in ducks and gout in goslings (Bidin, Lojkic, Tisljar, Bidin, & Majnaric, ; Liu et al, ; Jin et al, ; Liu, Jiang, Dong, Wang, & Zhang, ; Yang, Tian, Tang, & Diao, ; Zhang, Cao, et al, ; Zhang, Wang, Liu, Yang, & Zhang, ).…”

First Isolation and Molecular Characterization of Chicken Astrovirus and Avian Nephritis Virus in Chickens in Bangladesh

“…All CAstV and ANV of this study were clustered in a group of ORF1b polymerase gene phylogeny. Kaithal et al ( 46 ) analyzed the ORF1b genes of CAstV and ANV and revealed that Indian isolates of CAstV and ANV were aligned with circulating and Brazilian sequences of the respective viruses. It could be assumed that transboundary transmission of both viruses through neighboring borders may occur.…”

Molecular characterization of chicken astroviruses in gout-affected commercial broiler chickens in Haryana, India

“…Astroviruses have been detected from poultry flocks and other domestic birds from various parts of the world [8,10,15,19]. In a previous study conducted in our laboratory, we detected the presence of CAstV and ANV in enteritis-affected broiler chicken flocks by virus specific reverse-transcriptionpolymerase chain reaction (RT-PCR) [11].…”

“…The isolation and characterization of CAstV has been reported from broilers exhibiting RSS and dead-in-shell chicks having hatchability problems [1,29]. Few recent reports also suggest CAstVs infection in poultry in India [3,11,23].…”