title: Avian nephritis virus (ANV) on Brazilian chickens farms: circulating genotypes and intra-genotypic diversity.
abstract: Avian nephritis virus (ANV), which belongs to the family Astroviridae, is associated with different clinical manifestations (including enteric disorders). Despite being frequently found in the avian industry worldwide, information regarding genetic features of these viruses in Brazil is scarce. Therefore, sixty fecal sample pools (5-6 birds of the same flock), representing 60 poultry farms from six Brazilian States, were screened using an astrovirus-specific hemi-nested-PCR assay targeting the conserved ORF1b gene, followed by nucleotide sequencing of amplified products. PCR and phylogenetic analysis confirmed the detection of 21 positive samples to ANV (35 %). In order to investigate the genetic diversity represented by these viruses, amplification, cloning and phylogenetic analysis of the deduced amino acid sequence of ORF2 gene were attempted. Eight samples were successfully cloned (generating 32 clones in total) and sequenced. Based on phylogenetic analysis of ORF2, sequences defined in this study were classified into three genotypes: genotype 5, which has already been described in birds, and two other novel genotypes, tentatively named genotype 8 and 9, all of which occurred in single or mixed infections. Moreover, high intra-genotypic diversity and co-circulation of distinct strains in a same host population were observed. This study revealed the presence of new strains of ANV in Brazilian poultry and their circulation in commercial chicken flocks.
authors.affiliation: Department of Preventive Veterinary Medicine and Animal Health, College of Veterinary Medicine, University of São Paulo, Av. Professor Dr. Orlando Marques de Paiva, 87, Cidade Universitária, São Paulo, SP, Brazil. lunaluis@usp.br.
authors.forename: Luis Luna
authors.initials: LL
authors.lastname: Espinoza
authors.affiliation: Department of Preventive Veterinary Medicine and Animal Health, College of Veterinary Medicine, University of São Paulo, Av. Professor Dr. Orlando Marques de Paiva, 87, Cidade Universitária, São Paulo, SP, Brazil.
authors.forename: Laila A R
authors.initials: LA
authors.lastname: Beserra
authors.affiliation: Department of Preventive Veterinary Medicine and Animal Health, College of Veterinary Medicine, University of São Paulo, Av. Professor Dr. Orlando Marques de Paiva, 87, Cidade Universitária, São Paulo, SP, Brazil.
authors.forename: Rodrigo M
authors.initials: RM
authors.lastname: Soares
authors.affiliation: Department of Preventive Veterinary Medicine and Animal Health, College of Veterinary Medicine, University of São Paulo, Av. Professor Dr. Orlando Marques de Paiva, 87, Cidade Universitária, São Paulo, SP, Brazil.
authors.forename: Fabio
authors.initials: F
authors.lastname: Gregori
mesh_terms: D000818:Animals; D019350:Astroviridae Infections / Q000662:veterinary* / Q000821:virology; D052676:Avastrovirus / Q000145:classification* / Q000235:genetics*; D001938:Brazil; D002645:Chickens; D016000:Cluster Analysis; D000072480:Farms; D014644:Genetic Variation; D005838:Genotype; D016366:Open Reading Frames; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D011201:Poultry Diseases / Q000821:virology*; D017422:Sequence Analysis, DNA; D017385:Sequence Homology