Chicken proventricular necrosis virus (CPNV), formally known as Transmissible viral proventriculitis (TVP) virus, is a disease found in commercial broiler chickens and egg laying hens. It is a new birnavirus which was discovered in 2011. Since its discovery in 2011, the virus has been associated with other conditions such as runting and stunting syndrome. CPNV is a non-enveloped, double-stranded RNA virus.
CPNV causes proventricular glandular degeneration and epithelial necrosis, multifocal lymphocytic proventriculitis, and hyperplastic ductal epithelium. Tyical gross findings include
- Severe and diffuse thickening of the proventricular wall with prominent appearance of the glandular lobules.
- Circular areas of congestion and hemorrhage within the proventricular mucosa.
Microscopically, the most important lesions are restricted to the proventriculus, where necrosis of oxynticopeptic cells, lymphocytic infiltration, and hyperplastic ductal epithelium that replaces the glandular epithelium are commonly observed.