Detection of Turkey Astrovirus in Young Poults Affected with Poult Enteritis Complex in Brazil

Abstract

ABSTRACT. Reverse transcription polymerase chain reaction (RT-PCR) of turkey astrovirus (TAstV) capsid and polymerase genes was applied to the bursa of Fabricius (BF), thymus (TH), spleen (SP) and cloacal swabs (CS) of young poults with "Poult enteritis complex" (PEC). The histological lesions included atrophy, lymphoid depletion, cellular infiltration and necrosis of the BF, TH and SP, respectively. The RT-PCR reactions were positive for the polymerase gene of TAstV-2 in all 100 CSs, 7 out of 10 of BFs and 10 out of 20 THs and SPs, respectively. Five out of 10 THs and SPs samples, considered to be negative by RT-PCR, were positive when specific primers designed for the TAstV-2 capsid gene were applied. This is the first description of turkey astrovirus infection presenting PEC in Latin America. KEY WORDS: Brazil, poult enteritis complex, turkey astrovirus.

Experimental infection of poults and guinea fowl with genetically distinct avian astroviruses

“…thymus, spleen, bursa and caecal tonsils) in sacrificed poults at 4 days p.i. Findings from this study as well as from others may suggest an immunosuppressive role for these viruses (Tang et al, 2006;Da Silva et al, 2008;PantinJackwood et al, 2008b). However, it should be considered that TAstV2 can cause viraemia in infected turkeys (Pantin-Jackwood et al, 2008b).…”

“…A genetically and antigenically distinct type of turkey astrovirus was then identified in 1996 (Turkey astrovirus type 2 [TAstV2]) by Koci et al (2000a). Since these first detections, enteritis in turkey has been increasingly associated with the presence of astroviruses (Cattoli et al, 2007;Pantin-Jackwood et al, 2007, 2008aDa Silva et al, 2008;Jindal et al, 2010a), although high astrovirus prevalence has also been reported in apparently healthy turkey flocks (PantinJackwood et al, 2007(PantinJackwood et al, , 2008aJindal et al, 2010b;Domanska-Blicharz et al, 2011). TAstV2 appears to be the most common among the identified turkey astroviruses, while TAstV1 and avian nephritis virus* an astrovirus first described as responsible for nephritis in chicken (Imada et al, 2000)*have only been detected sporadically in turkey flocks (Pantin-Jackwood et al, 2007, 2008aDomanska-Blicharz et al, 2011).…”

Detection and molecular characterization of enteric viruses in breeder turkeys

“…All of these viruses have been reported from many countries from enteritis-affected commercial poults (McNulty et al, 1978(McNulty et al, , 1980aSaif et al, 1985, Reynolds & Saif, 1986Reynolds et al, 1987a,b;Barnes et al, 2000;Yu et al, 2000;Heggen-Peay et al, 2002;Teixeira et al, 2007;Da Silva et al, 2008, Jindal et al, 2009a. A few reports demonstrating the presence of these viruses in healthy flocks of commercial turkeys and chickens are also available (Reynolds et al, 1987b;Pantin-Jackwood et al, 2007, 2008a.…”

“…Due to these adverse effects, the economic losses to the US turkey industry are substantial. A number of viruses (coronavirus, reovirus, astrovirus, enterovirus, rotavirus, and adenovirus), bacteria (Escherichia coli and species of Salmonella, Clostridium, Campylobacter and Enterococcus) and protozoa (coccidia, cryptosporidium) have been detected in poult enteritis complex-affected flocks (Saif et al, 1985;Edens et al 1997;Barnes et al, 2000;Heggen-Peay et al, 2002;Pakpinyo et al, 2002;Barnes & Guy, 2003;McFerran, 2003;Guy et al, 2004;Da Silva et al, 2008). Experimental inoculation of poult enteritis complex material positive for enteric viruses, alone or in combination, caused diarrhoea and retarded growth and/or mortality in poults (Yason & Schat, 1986;Guy et al, 2000;Spackman et al, 2005;Pantin-Jackwood et al, 2008b).…”

First full-length sequences of the S gene of European isolates reveal further diversity among turkey coronaviruses

“…Many viruses other than TCoV have also been reported to be associated with enteritis in turkeys. These include, both in the Americas and in Europe, type 2 turkey astroviruses, picorna-like viruses, reoviruses, rotaviruses, and adenoviruses (Andral et al, 1985;Reynolds & Saif, 1986;Gough & Drury, 1998;Guy, 1998;Koci et al, 2000;Cattoli et al, 2007;Da Silva et al, 2008;PantinJackwood et al, 2008a;Woolcock & Shivaprasad, 2008;Jindal et al, 2009b). However, experimental studies with these agents inoculated alone Heggen-Peay et al, 2002;Pantin-Jackwood et al, 2008b;Gomaa et al, 2009) or in combinations (Yu et al, 2000;Jindal et al, 2009a;Spackman et al, 2010) seldom reproduce the whole range of signs observed in the diseased flocks.…”