title: Molecular typing of infectious bursal disease virus of Israeli field and vaccine strains by the reverse transcription/polymerase chain reaction/restriction fragment length polymorphism assay.
abstract: Infectious bursal disease viruses (IBDVs) were examined by testing bursa samples from 37 commercially reared chicken flocks and three vaccine strains by the reverse transcription (RT)/polymerase chain reaction (PCR)/restriction fragment length polymorphism assay (RFLP). The assay was conducted with a 717-bp fragment of the VP2 gene with the restriction enzymes BstNI and MboI. The presence of a restriction site for SspI was used to predict a very virulent phenotype. Results indicated the existence of two molecular groups within the field isolates; four samples showed one pattern of RFLPs, and the majority, 30 out of the 37 tested, showed a second RFLP pattern. Three samples tested negative for IBDV. Eight bursa samples, representing the two molecular groups, were also tested by the RT/PCR/RFLP assay as developed by Jackwood. A comparison of the RFLP profiles by the two methods indicated that four isolates belonged to molecular group 6 and 30 isolates belonged to a new molecular group. All field isolates had a very virulent phenotype. One vaccine strain, produced from a local isolate, was classified as molecular group 6. The other two vaccine strains had RFLPs that differed from those of the field isolates.
authors.affiliation: Division of Avian and Aquatic Animal Diseases, Kimron Veterinary Institute, Bet Dagan, Israel.
authors.forename: R
authors.initials: R
authors.lastname: Meir
authors.forename: D J
authors.initials: DJ
authors.lastname: Jackwood
authors.forename: Y
authors.initials: Y
authors.lastname: Weisman
mesh_terms: D000818:Animals; D002645:Chickens; D015252:Deoxyribonucleases, Type II Site-Specific / Q000378:metabolism; D007243:Infectious bursal disease virus / Q000145:classification*; D010641:Phenotype; D012150:Polymorphism, Restriction Fragment Length; D012367:RNA, Viral / Q000737:chemistry; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000662:veterinary*; D015678:Viral Structural Proteins / Q000235:genetics
chemical_list: D012367:RNA, Viral; C082513:VP2 protein, infectious bursal disease virus; D015678:Viral Structural Proteins; C046545:CCWGG-specific type II deoxyribonucleases; D015252:Deoxyribonucleases, Type II Site-Specific; C024405:GATC-specific type II deoxyribonucleases