1 INTRODUCTION
The emergence and dissemination of antimicrobial resistance (AMR) in the environment has become a global concern. Antimicrobial resistance (AMR) has been an area of focus during the past two decades and was recognizing AMR as a potential and serious threat for global public health among animals, environment and humans (Tacconelli et al., 2018). AMRs can be disseminated rapidly through various possible pathways, including foodborne pathogens, insects, wastewater, pet, food producing or wild animals, etc. (Q. E. Yang et al., 2019). In particular, more than 25 outbreaks of human infectious disease outbreaks were reported, 11 of which related to animals in farms, petting zoos and zoos during 1990 to 2000 (Bender & Shulman, 2004). Human may be infected by contacting wild animals directly or indirectly in some interactive activities of zoos, but this situation is easily ignored. The role of wild animals in zoos in the epidemiology of multidrug resistance (MDR) is a little concerned. Some previous studies have shown that bacterial isolates from wild animal living in human activity areas show stronger drug resistance compared with wild animals living in remote areas (Allen et al., 2011; Cole et al., 2005; Kozak, Boerlin, Janecko, Reid-Smith, & Jardine, 2009; Rolland, Hausfater, Marshall, & Levy, 1985; Skurnik et al., 2006). As a part of human urban life, the captive wild animals in zoos are obviously more closely contacted with human. Therefore, the captive animals in zoos may become a potential natural reservoir for AMRs and antibiotic resistant bacteria.
It is now abundantly clear that bacteria are able to meet the evolutionary challenge of combating antimicrobial chemotherapy, often by acquiring preexisting resistance determinants from the bacterial gene pool. This is achieved through the concerted activities of mobile genetic elements able to move within or between DNA molecules, which include insertion sequences, transposons, and gene cassettes/integrons, and those that are able to transfer between bacterial cells, such as plasmids and integrative conjugative elements. It has been proved that MDR bacteria from captive wild animals can carry various mobile genetic elements, such as IncI1 harboring bla CTX-M-1 and qnrS1 in E.coli from Czech zoo (Dobiasova et al., 2013), integron (class I and II) and plasmid carryingbla CMY-26,qnr and aac(6’)-Ib-cr in Gram-negative bacterial isolates from Japanese zoo(Ahmed et al., 2007), MDR Salmonella Enterobacter from captive wild animals and foreign animals in Ohio(Farias et al., 2015). It is suggested above that the emergence and dissemination of Multidrug Resistant pathogenic bacteria carried by wild animals in zoos may increase a serious public health risk between human, animal and environment.
To further understand the routes of dissemination of AMRs harboring bacteria in zoo, in the present study, fresh animal feces samples were collected and Enterobacteriaceae isolates were isolated in the routine monitoring of bacterial diseases in Zhengzhou zoo, Henan province, China. An MDR Klebsiella pneumoniae isolate from Red Kangaroo was severe drug resistance, including cephalosporins, such as the second generation cephalosporins (Cefuroxime Sodium ), the third generation cephalosporins (Ceftriaxone ) and even the fourth generation cephalosporins (Cefepime ). The whole genome sequencing (WGS) analysis was subjected to evaluate the relationship between its plasmid and drug-resistant gene related elements and human clinical isolates.