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

Abstract

<jats:title>Abstract</jats:title> <jats:p>Background. Transmissible viral proventriculitis (TVP) is an infectious disease reported in all production types of chickens. TVP is manifested in decreased body weight gains, wide weight diversity of birds in the flock and poor feed conversion. Histopathological examination seems to be the most reliable method for confirming the disease. Although TVP etiology has not been explicitly defined, a novel virus identified as a member of the <jats:italic>Birnaviridae</jats:italic> family, named chicken proventricular necrosis virus (CPNV) has been isolated from clinical cases of TVP and it is now considered as a potential factor of a disease. The study was undertaken in order to reproduce the disease under laboratory conditions and to evaluate the etiology of first described Polish case of TVP. Results. Anatomopathological and histopathological evaluation reveled that we've succeeded to reproduce TVP in broiler chickens. Within 14 days after infection birds gained approximately 30,38% less body weight in comparison to Control group. In TVP infected group a seroconversion against FAdV and IBDV was recorded 14 days post infection (dpi). 14 dpi CPNV was detected in proventriculi, while FAdV in spleens and livers of infected birds. Conclusions. We have demonstrated that CPNV was involved in the development of the disease. We did not record the presence of IBDV in the TVP or control birds, despite our recording a strong seroconversion against IBDV in the birds from the TVP group. CPNV belongs to the same family as IBDV, which allows us to assume serological cross-reactivity between them. This possibility of CPNV infections affecting IBDV antibody levels detected by commonly available ELISAs should be taken into account under poultry field conditions and diagnosis. The role of FAdV in the development of TVP needs further evaluation.</jats:p>