Molecular survey of enteric viruses in commercial chicken farms in Korea with a history of enteritis

Abstract

Several enteric viruses have increasingly received attention as potential causative agents of runting-stunting syndrome (RSS) in chickens. A molecular survey was performed to determine the presence of a broad range of enteric viruses, namely chicken astrovirus (CAstV), avian nephritis virus (ANV), chicken parvovirus (ChPV), infectious bronchitis virus (IBV), avian rotavirus (AvRV), avian reovirus (ARV), and fowl adenovirus (FAdV), in intestinal samples derived from 34 commercial chicken flocks that experienced enteritis outbreaks between 2010 and 2012. Using techniques such as PCR and reverse-transcription PCR, enteric viruses were identified in a total of 85.3% of investigated commercial chicken flocks in Korea. Furthermore, diverse combinations of 2 or more enteric viruses were simultaneously identified in 51.7% of chicken farms positive for enteric viruses. The rank order of positivity for enteric viruses was as follows: ANV (44.1%), CAstV (38.2%), ChPV (26.5%), IBV (20.6%), ARV (8.8%), AvRV (5.9%), and FAdV (2.9%). Additionally, other pathogens such as Escherichia coli, Salmonella spp., Eimeria spp., and FAdV were detected in 79% of chicken flocks positive for enteric viruses using PCR, bacterial isolation, and microscopic examination. The results of our study indicate the presence of several enteric viruses with various combinations in commercial chicken farms that experienced enteritis outbreaks. Experimental studies are required to further understand the roles of enteric viruses in RSS in commercial chickens.

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

“…In a subsequent study, however, these authors (Pantin-Jackwood et al, 2008) reported ARVs in 62.80% of the chicken flocks and 45.50% of the turkey flocks tested. Previous studies have reported the presence of ARV in intestinal/faecal samples of broiler chickens (Koo et al, 2013;Mettifogo et al, 2014) although most of these studies indicated low prevalence of ARV as compared to other enteric viruses.…”

“…Several pathogens such as avian rotavirus, astrovirus, reovirus, coronavirus, adenovirus, Salmonella, Escherichia coli, Enterococcus, and Eimeria spp. have been detected either alone or in different combinations from broiler chickens and turkey flocks afflicted with enteritis (Barnes et al, 2000;Jindal et al, 2010;Pantin-Jackwood et al, 2007, 2008Day and Zsak, 2013;Koo et al, 2013;Mettifogo et al, 2014).…”

“…Serological studies suggested widespread prevalence of ANV infections in commercial broiler chickens in various countries (Imada et al, 1980;Connor et al, 1987). In recent years, ANVs have been detected in enteritis-or RSS-affected broiler chickens from many different countries by molecular methods (Pantin-Jackwood et al, 2008;Smyth et al, 2009;Roussan et al, 2012;Koo et al, 2013;Mettifogo et al, 2014).…”

“…The detection/isolation of CAstVs has been reported from broiler chickens exhibiting RSS and from dead-in-shell chicks having hatchability problems (Baxendale and Mebatsion, 2004;Smyth et al, 2009;Pantin-Jackwood et al, 2011;Kang et al, 2012;Koo et al, 2013;Smyth et al, 2013;Mettifogo et al, 2014;SajewiczKrukowska et al, 2016). In most of these studies, CAstVs have been detected using reverse transcription PCR (RT-PCR) and/or quantitative RT-PCR targeting ORF1b or ORF2 genes.…”

“…The ARVs have been detected in enteritis-or RSS-affected broiler chickens (Davis et al, 2013;Koo et al, 2013;Mettifogo et al, 2014).…”