title: A survey for maintenance of virulent newcastle disease virus-free area in poultry production in Brazil.
abstract: In 2003, Brazil was recognized as a pathogenic Newcastle Disease Virus (NDV) strain-free country for commercial poultry. This research was conducted in Brazil between December 2003 and March 2005 to verify the maintenance of this virulent NDV-free status. Serum samples from 5,455 flocks for commercial poultry farms were collected, comprising 81,825 broiler chickens. The farms were located in nine states of the country, grouped in three geographic regions. Serological evidence of NDV infection was detected in 28.8% of the surveyed farms. However, all fifteen viruses isolated and identified as Newcastle Disease Virus (NDV) were characterized as nonpathogenic strains, based on the Intracerebral Pathogenicity Index. These results showed that Brazil preserves the virulent NDV-free status for commercial flocks.
authors.affiliation: Laboratório Nacional Agropecuário, Ministério da Agricultura, Pecuária e Abastecimento , Campinas, SP , Brasil ; Faculdade de Ciências Médicas, Universidade Estadual de Campinas , Campinas, SP , Brasil.
authors.forename: M A
authors.initials: MA
authors.lastname: Orsi
authors.forename: L
authors.initials: L
authors.lastname: Doretto
authors.forename: S C A
authors.initials: SC
authors.lastname: Camillo
authors.forename: D
authors.initials: D
authors.lastname: Reischak
authors.forename: S A M
authors.initials: SA
authors.lastname: Ribeiro
authors.forename: A
authors.initials: A
authors.lastname: Ramazzoti
authors.forename: A O
authors.initials: AO
authors.lastname: Mendonça
authors.forename: F R
authors.initials: FR
authors.lastname: Spilki
authors.forename: M G
authors.initials: MG
authors.lastname: Buzinaro
authors.forename: H L
authors.initials: HL
authors.lastname: Ferreira
authors.forename: C W
authors.initials: CW
authors.lastname: Arns
keywords: Newcastle Disease Virus; biological characterization; pathogenicity; poultry
references.citation: Arch Virol. 2002 May;147(5):1071-6
references.pmid: 12021875
references.citation: Avian Pathol. 2003 Oct;32(5):503-10
references.pmid: 14522706
references.citation: Br Poult Sci. 2001 Mar;42(1):5-22
references.pmid: 11337967
references.citation: Arch Virol. 2002 Aug;147(8):1655-63
references.pmid: 12181683
references.citation: Braz J Microbiol. 2010 Apr;41(2):349-57
references.pmid: 24031503
references.citation: Avian Dis. 2002 Jul-Sep;46(3):730-4
references.pmid: 12243542
references.citation: Avian Pathol. 1999 Jun;28(3):263-72
references.pmid: 26915382
references.citation: Avian Pathol. 1974 Oct;3(4):269-78
references.pmid: 18777282
references.citation: Prev Vet Med. 2006 Dec 18;77(3-4):199-214
references.pmid: 16950528
references.citation: Prev Vet Med. 2001 Jan 29;48(2):85-99
references.pmid: 11154782