Enterocytozoon Bieneusi,Cryptosporidium Spp. And Giardia Duodenalis In Dairy Cattle In Gansu,Northwestern Of China

Diarrhea of dairy cattle is the disease which caused by a variety of pathogens,and lead the animals to appeare the main symptom of diarrhea.Parasitic diseases as one of the main causes of its disease.It has already become a strong factor of hindering development of cattle industry on affecting the population of cattle breeding speed and economic lose,so it should be highly attentioned.Gansu province has a special location as it holds the upstream of the Yellow River,links up central and west China and impacts Central Asia.Gansu is an important agricultural province and have developed dairy farming industryin northwest China Due to its highland landscape in Gansu Province and its location in the center of the Silk Road,and nowadays,China’s milk is becoming an important consumer product as a substitute for many baby breast milk and adult nutrition.The Milk is an important source of food for zoonotic parasites.Therefore,it is very important to investigate the intestinal parasitic diseases in the dairy cattle in Gansu provinceTo reveal the epidemiological trait of the intestinal parasite in dairy cattle in Gansu province,a total of 2276 fecal samples were collected from 12 sites of Gansu province,The total infection rate of seven kinds of intestinal parasites identified by the screening was 37.4%(851/2276).The predominant parasite was amoeba protozoa with the infection rate 23.6(537/2276),and the infection rates of coccidian,Cryptosporidium spp.,Giardia duodenalis,Strongylid spp.,whipworm and tapeworm were 14.5%(329/2276),1.8%(42/2276),0.1%(2/2276),1.8%(42/2276),0.8%(18/2276)and 0.2%(4/2276),respectively.Enterocytozoon bieneusi,Cryptosporidium spp.,and Giardia duodenalis are three zoonotic parasites,which can causing diarrhea in various mammals including human and dairy cattle.To study the molecular epidemiology of these three zoonotic protozoans in dairy cattle in Gansu province,which located in the plateau areas of northwestern China and situated the center of ancient Silk Road,a total of 1414 fresh fecal specimens(43 Ypositive samples,582 Pre-weaned and 789 negative samples examed by microscopic of heifers and adult cattle)were collected for screening.The results showed that the prevalence of E.bieneusi,Cryptosporidium spp.,and G.duodenalis was 22.6%(320/1414),3.1%(44/1414),and 1.0%(14/1414)by polymerase chain reaction(PCR)amplification,respectively.The survey showed that there were three kinds of intestinal protozoa in the dairy cattle,except that the G.duodenalis was found in adult cattle.The highest rates of Cryptosporidium spp.and G.duodenalis were in the pre-weaned calves,and there was no significant difference in the rate of E.bieneusi infection in different age cattle.In addition,different clinical diarrhea symptoms associated with these three intestinal parasitic infection rate.For E.bieneusi,a total of eight genotypes were found based on internal transcribed spacer(ITS)gene,includinghree novel:CGC1,CGC2,CGC3.And five known genotypes:J,I,BEB8,BEB10(CM 19),CM21.Phylogenetic analysis revealed that all the genotypes identified in present study were clustered in Group 2 with potential zoonotic,CGC1 is on the same branch as the genotype J and 1 of Group2 found in the human body.Four Cryptosporidium species were found based on the small subunit rRNA(SSU rRNA)gene,including C.parvum,C.andersoni.C.bovis and C.ryanae The C.parvum in dairy cattle includ two subtypes(IIdA15G2R1 and IIdA19G1)based on 60 kDa glycoprotein(gp60)gene.All the G.duodenalis detected in this study belonged to Assemblage E based on the small subunit rRNA(SSU rRNA)and triosephosphate isomerase(tpi)gene.In conclusion,all three protozoan identified in dairy cattle had potential zoonotic risk.It’s also useful to establish a safe and effective precaution mechanism to offer a theoretical principle for its prevention and control in northwestern plateau of China,which as the important node of Chinese"One Belt and One Road" strategy.