Tuyển tập các báo cáo nghiên cứu khoa học quốc tế về bệnh thú y đề tài: Genetic analysis of ORF5 of recent Korean porcine reproductive and respiratory syndrome viruses (PRRSVs) in viremic sera collected from MLV-vaccinating or non-vaccinating farms | J. Vet. Sci. 2009 10 2 121-130 DOI JOURNAL OF Veterinary Science Genetic analysis of ORF5 of recent Korean porcine reproductive and respiratory syndrome viruses PRRSVs in viremic sera collected from MLV-vaccinating or non-vaccinating farms 1 t 3 t 1 1 1 2 Hye Kwon Kim Jeong Sun Yang Hyoung Joon Moon Seong Jun Park Yuzi Luo Chul Seung Lee Dae 2 2 1 1 1 Sub Song Bo Kyu Kang Soo Kyung Ann Chan Hyuk Jun Bong Kyun Park Department of Veterinary Medicine Virology Lab College of Veterinary Medicine and BK21 Program for Veterinary Science Seoul National University Seoul 151-742 Korea 2Research Unit Green Cross Veterinary Products Yongin 449-903 Korea 3Center for Infectious Diseases Korea National Institute of Health Seoul 122-701 Korea The 23 open reading frame ORF 5 sequences of Korean type II porcine reproductive and respiratory syndrome virus PRRSV were collected from viremic sera from the modified live vaccine MLV-vaccinating and non-vaccinating farms from 2007 to 2008. The samples were phylogenetically analyzed with previous ORF5 sequences including type I Korean PRRSV and previously reported or collected sequences from 1997 to 2008. A MN184-like subgroup of type II Korean PRRSV was newly identified in the viremic sera collected from 2007 to 2008. And of the type I PRRSVs one subgroup had similarity with the Lelystad virus showing a close relationship with the 27 2003 strain of Spain. The maximum parsimony tree of type II PRRSV from 1997 to 2008 showed that they had evolved to four lineages subgroups 1 2 3 and 4. Most of the recently collected type II PRRSVs belonged to subgroup 4 48 . The region of three B-cell epitopes and two T-cell epitopes of ORF5 amino acids sequences was considerably different from the MLV in subgroups 3 and 4. In conclusion the existence of type I PRRSV which was genetically different from Lelystad virus Prototype of type I PRRSV and heterologous type II PRRSVs of viremic pigs detected even in the .
