Chen Danyu, Zou Wencheng, Xie Shengze, Kong Linghan, Chen Yanpeng, Zhang Xiuzhong, Li Jianan, Wang Hongning, Cheng Guangyang, Qin Yue, Mu Xingyu, Yang Xin
1 Key Laboratory of Bio-Resource and Eco-Environment of the Ministry of Education, Animal Disease Prevention and Food Safety Key Laboratory of Sichuan Province, College of Life Sciences, Sichuan University, Chengdu 610065, Sichuan, People's Republic of China.
J Wildl Dis. 2018 Oct;54(4):691-699. doi: 10.7589/2017-07-165. Epub 2018 May 9.
Escherichia coli is a major pathogen leading to systemic and enteric illnesses in wild giant pandas ( Ailuropoda melanoleuca). To investigate the characteristics and distribution of E. coli in wild giant pandas across four different nature reserves in Sichuan, Republic of China, we researched serotypes, phylogenetic groups, antimicrobial resistance, and resistance genes of E. coli not previously reported for wild giant pandas. A total of 82 E. coli isolates were identified from 40 fecal samples in August 2016 to May 2017. The most-prevalent serogroups were O15 (4%, 3/82), O28 (2%, 2/82), and O44 (2%, 2/82). Antimicrobial resistance was highest for streptomycin (61%, 50/82) followed by amikacin (30%, 25/82). Among the four nature reserves, the proportion of streptomycin (86%, 12/14) and amikacin (57%, 8/14) was highest in Liziping. The frequencies of resistant genes aph(3')-IIa, ant(3″)-Ia, aac(3)-IIa, aadA1, and StrB were 28, 23, 5, 21, and 32%, respectively, while none of the strains had the tetracycline gene. In Qianfoshan, the phylogenetic group B2 was the most common, comprising the highest percentage of isolates compared with the other seven phylogenetic groups. Furthermore, many variables such as phylogenetic groups, antimicrobial susceptibility, and resistance genes differed significantly ( P<0.05) among the four nature reserves. In facilitating the safe discharge of captive giant pandas into the wild, as well as to support existing wild populations, the data from this research will prove invaluable to scientists and ecologists in their endeavors.
大肠杆菌是导致野生大熊猫（大熊猫）出现全身性和肠道疾病的主要病原体。为了调查中国四川省四个不同自然保护区野生大熊猫体内大肠杆菌的特征和分布情况，我们研究了野生大熊猫中尚未报道过的大肠杆菌血清型、系统发育群、抗菌药物耐药性和耐药基因。2016年8月至2017年5月期间，从40份粪便样本中共鉴定出82株大肠杆菌分离株。最常见的血清群为O15（4%，3/82）、O28（2%，2/82）和O44（2%，2/82）。对链霉素的耐药率最高（61%，50/82），其次是阿米卡星（30%，25/82）。在四个自然保护区中，链霉素（86%，12/14）和阿米卡星（57%，8/14）的耐药率在栗子坪最高。耐药基因aph(3')-IIa、ant(3″)-Ia、aac(3)-IIa、aadA1和StrB的频率分别为28%、23%、5%、21%和32%，而所有菌株均未携带四环素基因。在千佛山，系统发育群B2最为常见，与其他七个系统发育群相比，其分离株所占百分比最高。此外，四个自然保护区之间的许多变量，如系统发育群、抗菌药物敏感性和耐药基因，差异显著（P<0.05）。在促进圈养大熊猫安全放归野外以及支持现有野生种群方面，本研究的数据将对科学家和生态学家的工作具有巨大价值。
