Zhou Yuanyuan, Song Shuti, Li Weihuo, Jia Yixin, Li Yangshuo, Liang Jingyi, Yao Zhaofeng, Zhang Nan
Department of Life Science and Engineering, Foshan University, 52800 Foshan, China.
J Vet Res. 2024 Nov 28;68(4):497-508. doi: 10.2478/jvetres-2024-0065. eCollection 2024 Dec.
(MG) infection is a primary cause of chronic respiratory disease in poultry, threatening the economic viability of China's goose-farming industry. This study investigated the pathogenicity and drug resistance of an MG strain isolated from geese and whole-genome sequenced the strain.
A strain designated MG-GD01/22 was isolated from the air-sac tissues of five geese with chronic respiratory disease on a Guangdong goose farm. Its pathogenicity was assessed, antimicrobial susceptibility tests were performed using agar dilution, and its total DNA was extracted for whole-genome sequencing and gene function annotation with second- and third-generation sequencing technologies. The homology of the 16S ribosomal RNA (rRNA) region was analysed and a phylogenetic tree was constructed, as was an evolutionary tree of the gene. Gene co-linearity analysis was performed to compare MG-GD01/22 with the strains in the GenBank database.
The isolate produced "fried egg" colonies and was pathogenic to goslings. It was resistant to enrofloxacin, danofloxacin and spectinomycin and susceptible to valnemulin, tilmicosin, tylosin, acetylisovaleryltylosin tartrate and tiamulin. The genome analysis revealed 1,666 coding genes. Gene database annotation identified 25 virulence-related genes, 22 drug resistance-related genes, 13 pathogen-host-interaction genes and 9 carbohydrate-active enzyme genes. The isolate exhibited 99.9% homology to the MG S6 strain by its 16S rRNA, while the gene typing results indicated that it differed from known MG model strains. The genome of MG-GD01/22 showed high homology but poor co-linearity with MG S6, characterised by numerous gene deletions, inversions and displacements.
This study offers theoretical references for the diagnosis, prevention and treatment of MG in geese in the Guangdong region.
支原体（MG）感染是家禽慢性呼吸道疾病的主要病因，威胁着中国养鹅业的经济可行性。本研究调查了从鹅分离出的一株MG菌株的致病性和耐药性，并对该菌株进行了全基因组测序。
从广东一个养鹅场的5只患有慢性呼吸道疾病的鹅的气囊组织中分离出一株命名为MG-GD01/22的菌株。评估其致病性，采用琼脂稀释法进行药敏试验，并提取其总DNA，使用二代和三代测序技术进行全基因组测序和基因功能注释。分析16S核糖体RNA（rRNA）区域的同源性并构建系统发育树，以及该基因的进化树。进行基因共线性分析以将MG-GD01/22与GenBank数据库中的菌株进行比较。
该分离株产生“煎蛋”菌落，对雏鹅具有致病性。它对恩诺沙星、达氟沙星和壮观霉素耐药，对沃尼妙林、替米考星、泰乐菌素、酒石酸乙酰异戊酰泰乐菌素和替米考星敏感。基因组分析揭示了1666个编码基因。基因数据库注释鉴定出25个毒力相关基因、22个耐药相关基因、13个病原体-宿主相互作用基因和9个碳水化合物活性酶基因。该分离株通过其16S rRNA与MG S6菌株表现出99.9%的同源性，而基因分型结果表明它与已知的MG模型菌株不同。MG-GD01/22的基因组与MG S6显示出高度同源性但共线性较差，其特征是存在大量基因缺失、倒位和移位。
本研究为广东地区鹅MG的诊断、预防和治疗提供了理论参考。
