title: Evidence for virus closely related to avian myeloblastosis-associated virus type 1 in a commercial stock of chickens.
abstract: A two-round nested polymerase chain reaction assay detected Rous associated virus-1 (RAV-1), a prototype laboratory strain of avian leukosis virus of subgroup A (ALV-A). Surprisingly, the test failed to detect three field isolates of ALV-A but did detect virus in one commercial stock of chickens (stock F). The sequence analysis of a core of 290 nucleotides of the env gene gave evidence that the virus from stock F was closely related to avian myeloblastosis-associated virus type one (MAV-1). Other primers were used to amplify and sequence a 1491 nucleotide fragment of the env gene, and a 1245 nucleotide portion of this sequence used for a phylogenetic comparison. These analyses on 10 chickens gave evidence that six were infected with MAV-1-like virus and three with RAV-2 (subgroup B virus), and one chicken with a mixture of the two viruses. Tests with primers designed specifically for the MAV-1 sequence at a pre-determined target site and a second primer designed specifically for RAV-2 at the same site gave further evidence that the viruses isolated from stock F were closely related to one or other of these two viruses.
authors.affiliation: Canadian Food Inspection Agency, Ottawa Laboratory Fallowfield, Animal Diseases Research Institute, 3851 Fallowfield Road, Ottawa, Ontario, Canada K2H 8P9. spencerl@inspection.gc.ca
authors.forename: J Lloyd
authors.initials: JL
authors.lastname: Spencer
authors.forename: Bernhard
authors.initials: B
authors.lastname: Benkel
authors.forename: Maria
authors.initials: M
authors.lastname: Chan
authors.forename: Susan
authors.initials: S
authors.lastname: Nadin-Davis
mesh_terms: D000818:Animals; D001354:Avian Leukosis Virus / Q000145:classification / Q000235:genetics / Q000302:isolation & purification; D009189:Avian Myeloblastosis Virus / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*; D001483:Base Sequence; D002645:Chickens / Q000821:virology*; D008969:Molecular Sequence Data; D010802:Phylogeny; D016133:Polymerase Chain Reaction / Q000662:veterinary