Molecular Characterization and Pathogenicity of Chicken Parvovirus (ChPV) in Specific Pathogen-Free Chicks Infected Experimentally

Abstract

Chicken parvovirus (ChPV) is an agent frequently associated with runting stunting syndrome (RSS). This syndrome has been reported in association with ChPV in many countries, including Brazil; however, studies characterizing the virus on a molecular level are scarce, and ChPV pathogenicity in day-old chicks remains unclear. The aim of the present work was to establish the molecular characteristics of ChPV, determine the pathogenicity of ChPV in SPF chicks and detect and quantify ChPV by qPCR in several tissues and chicks of different ages. The experimental challenge was performed at one day of age, and daily and weekly observations were performed and five birds from each experimental group (mock and infected birds) were euthanized to perform the different analysis. ChPV genome copies were detected and quantified by qPCR in gut, spleen, thymus, kidney, pancreas, proventriculus and bursa. Clinically, the infected group presented with diarrhea 24 h post-infection, which persisted until 42 days of age. The small intestine was distended, and its contents were aqueous and foamy. Enteritis and dilated crypts with cyst shapes were observed in intestinal segments. Acute pancreatitis associated with lymphocytic nodules, infiltrating lymphocytes and plasma cells between the pancreatic acinus was observed. Koch’s postulate was demonstrated and the genetic characterization of the VP1 gene showed that the Brazilian ChPV isolate belongs to the ChPV II group.

Development and application of TaqMan probe‐based quantitative PCR assays for the detection of tilapia parvovirus

“…Since the NS and VP genes represent major proteins and are well conserved in viruses in the family Parvoviridae , they are often used to design specific primers and probes for TaqMan qPCR assays in pig, dog and duck (Song et al., 2010; Sun et al., 2018; Wan et al., 2018). Nonetheless, the genetic variations at the binding sites of primers and probes could affect the diagnostic performance, as shown with Muscovy duck parvovirus (MDPV) and chicken parvovirus (ChPV) (Nuñez et al., 2020; Wan et al., 2018). In the present study, the primers and probes were designed based on conserved sequences of the NS and VP genes of TiPV from Thailand and China (Du et al., 2019; Liu et al., 2020; Yamkasem et al., 2021a).…”

Molecular Characterization of the Chicken Parvovirus Based on VP1 Gene Circulating in Brazilian Chicken Flocks

“…These differences in similarity of NT are in accordance with previous studies of ChPV genotyping [ 8 ]. Recombination of DNA plays an important role in rapid viral evolution and has important implications for disease evolution [ 32 ]. These events could cause transformations in the genome that could translate into new strains that escape the host immune response provided by a vaccine or could cause different effects in tissues or in the presentation of diseases [ 26 , 32 , 33 ].…”

Establishment of a TaqMan probe‐based qPCR assay for detecting microsporidia Enterospora epinepheli in grouper

“…Furthermore, the TaqMan qPCR method is more specific than SYBR Green qPCR method because it adds the addition of probes specific for the pathogen under test. In particular, TaqMan probe‐based qPCR is less prone to produce false‐positive results in co‐infected samples, which are common in fish disease investigations (Nuñez et al., 2020; Yamkasem et al., 2021). It will greatly facilitate subsequent epidemiological investigations.…”