Detection And Molecular Identification Of Three Intestinal Pathogens In Wild Animals In Beijing Zoo

Giardia duodenalis,Enterocytozoon bieneusi and Blastocystis.SPP are common intestinal pathogens in humans and animals,which mainly cause host diarrhea and growth retardation.The three pathogens have a wide range of hosts and can infect humans,livestock,poultry,companion animals and wildlife,mostly through fecal-oral transmission.Wildlife is the precious wealth of nature.Zoo plays an indispensable role in protecting the diversity of animal species.In this study,molecular biological methods were used to detect the infection of three intestinal pathogens in captive wild animals in Beijing Zoo,identify their genotypes/subtypes,and analyze their molecular genetic characteristics.Based on the SSU r RNA gene locus of Giardia duodenalis,the fecal DNA samples of 441 captive wild animals in Beijing Zoo were detected by PCR.The results showed that 17 samples were positive for Giardia duodenalis,and the infection rate was 3.9%(17/441).The infection rate of mammals was 5.3%(17/318),and no Giardia duodenalis was detected in birds.There was no significant difference in infection rates among different categories of animals(P> 0.05).Through sequence alignment analysis,three kinds of Giardia duodenalis assembles were identified,which were zoonotic assemble A(n=1)and assemble B(n=13),and ruminant specific assemble E(n=3).The results showed that the infection rate of Giardia duodenalis in wild animals in Beijing Zoo was low,and there was zoonotic assemble.Based on the ITS locus of Enterocytozoon bieneusi.441 fecal DNA samples were detected by PCR.It was found that 32 samples were positive for Enterocytozoon bieneusi.and the infection rate was7.3%(32/441),including 7.5%(24/318)of mammals and 6.5%(8/123)of birds.There was no significant difference(P>0.05).Through sequence alignment analysis,13 known genotypes of Enterocytozoon bieneusi.were identified,including human zoonotic genotypes Ebp A(n=7),MJ13(n=1),Pig EBITS7(n=2),CM16(n=1),type IV(n=7),D(n=2),SCO2(n=3),HND-1(n=1)and BEB6(n=2),and specific genotypes CM4(n=2),CHB1(n=2),WL2(n=1)and CHK1(n=1).The results suggest that there are genotypic diversity and distribution characteristics of Pichia pastoris in wild animals in Beijing Zoo,which is consistent with the investigation results of other zoos in China.Based on the SSU r RNA gene locus of Blastocystis,PCR was used to detect 441 fecal DNA samples,and 68 samples were found to be positive for Blastocystis,with an infection rate of 15.4%(68/441).Among them,20.1%(64/318)of mammals and 3.3%(4/123)of birds were significantly different(P<0.01).Through sequence alignment analysis,10 subtypes of Blastocystis were identified,which were zoonotic subtypes ST1(n=13),ST2(n=17),ST3(n=2),ST4(n=3),ST6(n=1),ST7(n=3)and ST8(n=4),and specific subtypes ST10(n=18),ST11(n=6)and ST23(n=1)only infected animals.The results suggested that the infection of wild animals in Beijing Zoo was relatively common,and its subtype distribution had certain host specificity.In summary,this study found that the infection rates of Giardia duodenalis and Enterocytozoon bieneusi in captive wild animals in Beijing Zoo were low,and the infection of Blastocystis.SPP was common.Genotypes/subtypes of intestinal Enterocytozoon bieneusi and Blastocystis.SPP have diverse genetic distribution characteristics,and have certain host specificity.The results provide basic data for the epidemiology and molecular characteristics of wild animal intestinal pathogens in zoos in China.