College of Animal Science, South China Agricultural University, Guangzhou, 510642, P.R. China.
Key Laboratory of Chicken Genetics, Breeding and Reproduction, Ministry of Agriculture, Guangzhou, 510642, P.R. China.
Sci Rep. 2017 Jul 26;7(1):6576. doi: 10.1038/s41598-017-06987-2.
Two hundred and six strains of avian infectious bronchitis virus (IBV) were isolated from chickens showing signs of disease in southern China during the period from 2013-2015. The nucleotide and amino acid sequences from the isolated field strains were compared to 42 published references. Nucleotide homologies ranged from 63.1-99.9% and amino acid homologies ranging from 60.2-100%. At least seven IBV genotypes were co-circulating in commercial chicken farms in southern China. The IBV isolates were genetically diverse and underwent continuing evolution. The QX-type, TW I-type, and 4/91-type were the most common genotypes during the three-year observation period and accounted for 88.8% of the isolated strains. Notably, the prevalence of the TW I-type strains has been increasing in recent years and has become the most common genotype in China. The emergence of variant IBV strains can be attributed to recombination. Serologic analysis and antigenic 3D cartography of 4 reference and 14 field isolated strains indicated the surveyed IBVs had diverse serology types and that the serotype of the isolated QX-type and TW I-type strains was distinct from the vaccines strains. Therefore, long-term continuing surveillance is necessary for IBV prevention and control.
从 2013 年至 2015 年，中国南方地区出现疾病症状的鸡群中分离到 206 株禽传染性支气管炎病毒（IBV）。将分离的田间毒株与 42 株已发表的参考株的核苷酸和氨基酸序列进行比较。核苷酸同源性为 63.1-99.9%，氨基酸同源性为 60.2-100%。至少有七种 IBV 基因型在中国南方的商业鸡场中共同流行。IBV 分离株具有遗传多样性，并不断进化。在三年的观察期内，QX 型、TW I 型和 4/91 型是最常见的基因型，占分离株的 88.8%。值得注意的是，近年来 TW I 型株的流行率一直在增加，已成为中国最常见的基因型。变异 IBV 株的出现可归因于重组。对 4 株参考株和 14 株田间分离株进行血清学分析和抗原 3D 图谱分析表明，所检测的 IBV 具有不同的血清型，分离的 QX 型和 TW I 型株的血清型与疫苗株不同。因此，需要对 IBV 进行长期持续监测，以预防和控制该病。
