一株黑叶猴源鸟肠球菌的分离鉴定及耐药分析

Isolation, identification and drug resistance analysis of a strain of Enterococcus avium from Trachypithecus francoisi

黑叶猴是我国一级重点保护动物,2018年11月贵州某动物园中黑叶猴出现死亡,为调查其原因,本研究采集病死黑叶猴的肺脏样品进行细菌分离纯化,并对分离菌进行革兰氏染色镜检、生化鉴定、16S rRNA基因序列鉴定、小鼠致病性试验及分离株的药敏试验和耐药基因检测。结果显示:经形态观察、培养特性鉴定以及16S r RNA的PCR鉴定,该分离株为鸟肠球菌,将其命名为GZ1811;16S rRNA基因的同源性分析及进化树结果显示,GZ1811株与GenBank中鸟肠球菌的一致性为100%;小鼠致病性试验结果显示,小鼠出现临床症状,甚至死亡,解剖可见其肺脏有散在出血点;药敏试验结果显示,分离株对四环素等药物耐药。耐药基因PCR检测结果显示分离菌株的四环素类耐药基因tetM呈阳性,表明耐药表型和耐药基因型一致。本实验为黑叶猴鸟肠球菌病的诊断和防治提供具有科学价值的参考依据。

The Trachypithecus francoisi is one of the national first-level key protected animals in China. To investigate the cause of death of the trachypithecus francoisi in a zoo of Guizhou in November 2018, lung samples of sick and dead Trachypithecus francoisi were collected for bacterial isolation and purification, and the isolates were subjected to Gram staining and microscopic examination, biochemical identification, 16 S rRNA gene sequence identification, mouse pathogenicity test, drug sensitivity test, and resistance gene detection. The results showed that the isolated strain was identified as Enterococcus avium after morphological observation, identification of culture characteristics and PCR identification of 16 S rRNA, and was named GZ1811;homology analysis and phylogenetic tree of 16 S rRNA gene results showed that the GZ1811 strain was 100% consistent with Enterococcus avium in GenBank. The mouse pathogenicity test results showed that the mice developed clinical symptoms and even die, and anatomy revealed scattered bleeding points in the lungs. The drug sensitivity test results showed that the isolates were resistant to tetracycline and other drugs. The PCR amplification of the resistance gene showed that the tet M gene was positive,indicating that the resistance phenotype was consistent with the resistance genotype. This research has a certain scientific value in the diagnosis and prevention Enterococcus avium disease in the feeding of Trachypithecus francoisi, and provides reference for the diagnosis and prevention of the bacteria in the feeding of Trachypithecus francoisi.