Toplak Ivan, Sandvik Torstein, Barlic-Maganja Darja, Grom Joze, Paton David J
Department of Virology, Veterinary Faculty, 1115 Ljubljana, Slovenia.
Vet Microbiol. 2004 Apr 19;99(3-4):175-85. doi: 10.1016/j.vetmic.2003.12.004.
A selection of 43 bovine viral diarrhoea viruses isolated from mainly persistently infected cattle on 23 Slovenian farms between 1997 and 2001 were characterised genetically. Viral RNA was extracted from infected cell cultures, reverse transcribed and amplified by PCR with primers targeting the 5'-UTR and the N(pro) gene, followed by direct sequencing of purified PCR products obtained for both genomic regions. The N(pro) sequences provided the best genetic resolution, and gave also higher statistical support for phylogenetic classification of the viruses. Thirty-eight of the Slovenian isolates were of genetic subtypes 1d and 1f, four were 1b, and one subtype 1g. No BVDV type 2 viruses were found. This genetic prevalence matched those previously reported for neighbouring countries, as opposed to findings reported for more distant European countries, e.g. France, Spain and the UK. From eight cattle herds several virus isolates were analysed; with one exception all isolates from each herd were of the same genetic group. Extended sequencing of the N(pro) and part of the C gene of virus isolates with identical 5'-UTR sequences allowed differentiation between isolates obtained at different times from one herd.
对1997年至2001年间从斯洛文尼亚23个农场主要持续感染牛群中分离出的43株牛病毒性腹泻病毒进行了基因特征分析。从感染的细胞培养物中提取病毒RNA，逆转录并用靶向5'-UTR和N(pro)基因的引物通过PCR扩增，随后对两个基因组区域获得的纯化PCR产物进行直接测序。N(pro)序列提供了最佳的遗传分辨率，并且对病毒的系统发育分类也提供了更高的统计支持。斯洛文尼亚分离株中有38株属于基因亚型1d和1f，4株为1b，1株为亚型1g。未发现2型牛病毒性腹泻病毒。这种基因流行情况与邻国先前报道的数据相符，与更远的欧洲国家如法国、西班牙和英国报道的结果相反。对8个牛群的多个病毒分离株进行了分析；除一个例外，每个牛群的所有分离株都属于同一基因群。对具有相同5'-UTR序列的病毒分离株的N(pro)和部分C基因进行扩展测序，可以区分同一牛群在不同时间获得的分离株。
