Detection of Chicken Proventricular Necrosis Virus (R11/3 Virus) in Experimental and Naturally Occurring Cases of Transmissible Viral Proventriculitis with the Use of a Reverse Transcriptase-PCR Procedure

Abstract

A reverse-transcriptase-polymerase-chain-reaction (RT-PCR) procedure was evaluated for detection of chicken proventricular necrosis virus (CPNV) in transmissible viral proventriculitis (TVP) -affected chickens. The RT-PCR procedure was compared with indirect immunofluorescence (IFA) and virus isolation for detection of CPNV in experimentally infected chickens. Microscopic lesions characteristic of TVP were detected on days 5-35 postexposure (PE) in CPNV-infected chickens; CPNV was detected by RT-PCR on days 3-14 PE in freshly collected proventriculi, and on days 1-14 PE in formalin-fixed paraffin-embedded (FFPE) proventriculi. CPNV was detected in proventriculi of experimentally infected chickens by IFA on days 3-10 PE, and by virus isolation on days 1-14 PE. With IFA used as a reference, sensitivity of the RT-PCR procedure with freshly collected and FFPE proventriculi was 88% and 100%, respectively; specificity was 83% and 86%, respectively. Proventriculi (FFPE) obtained from suspect TVP cases (n=19) were evaluated for presence of CPNV by RT-PCR and microscopic lesions consistentwith TVP. CPNV was detected by RT-PCR in proventriculi from 8/11 TVP (+) cases (24/36 tissue sections). TVP (+) cases were defined by microscopic lesions characteristic of TVP; CPNV was not detected in proventriculi (0/8 cases, 0/32 tissue sections) in the absence of these lesions. The association between presence of TVP-characteristic microscopic lesions and presence of CPNV was highly significant (P = 0.0014). These findings indicate the utility of the RT-PCR procedure for detection of CPNV and provide additional evidence for an etiologic role for this virus in TVP.

Detection of transmissible viral proventriculitis and chicken proventricular necrosis virus in the UK

“…TVP was first described in the Netherlands almost 40 years ago (Kouwenhoven et al, 1978). Since then, it has been reported in several countries in North America (Guy et al, 2011b;Noiva et al, 2015), Europe (Grau-Roma et al, 2010;Marguerie et al, 2011), and Asia (Kim et al, 2015). Since the emergence of the disease, there has been considerable discussion as to the aetiological agent responsible.…”

“…Several viruses have been suggested including: an adenovirus (Kouwenhoven et al, 1978), a reovirus (Jones, 2000), infectious bronchitis virus (Yu et al, 2001), infectious bursal disease virus (IBDV) (Huff et al, 2001), and a picornavirus (Kim et al, 2015). A few years ago, a new birnavirus, named chicken proventricular necrosis virus (CPNV), was detected in naturally and experimentally reproduced TVP-affected cases in the USA and proposed to be its cause (Guy et al, 2011a(Guy et al, , 2011b. CPNV has subsequently been detected in a few other studies in TVP-affected broiler chickens in France and the USA (Marguerie et al, 2011;Noiva et al, 2015).…”

Chicken proventricular necrosis virus related transmissible viral proventriculitis in broiler chickens in Poland

“…However, based on the phylogenetic studies of the VP1 gene, it has been established that this virus is different from other known members of this family of viruses. It is interesting that clinical TVP was reproduced with the use of isolated CPNV [7].…”

“…It remains unknown, however, if all cases of this disease are of the same infectious origin. There are cases of TVP in which CPNV cannot be identi ed, as well as disease cases in which CPNV can be identi ed but which do not meet the diagnostic criteria of TVP [7,11,12]. In addition, it is suggested that the pathogenesis of TVP could be more complex and may result from other viral, bacterial or fungal co-infections [1].…”

“…The rst reports on TVP date back to 1978 and come from the Netherlands [2], when Kouwenhoven et al reported a case of proventriculitis in commercial chicken broilers and proved that TVP was induced by an infectious factor. Since then, TVP cases have been identi ed and reported in the USA, Australia, China, South Korea, Spain, France, the UK, and Poland among other countries [3][4][5][6][7][8][9][10].…”