Molecular Epidemiological Investigation And Genetic Evolution Analysis Of Major Intestinal Protozoa Diseases Of Pigs In Jilin Province

Cryptosporidium,Giardia,Blastocystis and Enterocytozoon bieneusi are important zoonotic intestinal protozoa,which are prevalent worldwide.The main transmission route of the four intestinal protozoa is fecal-oral transmission,and the infected hosts are extensive,including humans,mammals,birds and reptiles.Pigs are the main hosts of these four intestinal protozoans,which can infect a variety of zoonotic genotypes / species,and are potential sources of infection for humans.In this study,polymerase chain reaction(PCR)was used to investigate the prevalence of Cryptosporidium,Giardia,Blastocystis and Enterocytozoon bieneusi in pigs in Jilin Province by detecting 1039 fecal samples of pigs in Jilin Province,results are as follows:The total infection rate of Cryptosporidium was 6.45 %(67/1039).The infection rate of suckling piglets was the highest(10.74%).The infection rates of nursery pigs and fattening pigs were 6.94% and 5.54%,respectively.The infection rate of sows was the lowest(4.17%).Among different regions,Jilin City had the highest infection rate of 8.51%.Changchun had the lowest infection rate of 4.99%.The infection rates in Yanji,Baicheng and Siping were 7.94%,7.70% and 6.55%,respectively.In different seasons,the highest infection rate was 8.33% in spring.The lowest infection rate was 5.07% in summer.The infection rates in autumn and winter were 6.21% and7.92%,respectively.The infection rate of Cryptosporidium in pigs in 2021 was 8.27%higher than 5.86% in 2022.The results of statistical analysis showed that there was no significant difference in the infection rate of Cryptosporidium in pigs in different regions,different years and different seasons(P > 0.05).In this study,three Cryptosporidium species were detected,namely Cryptosporidium suis(n=24),Cryptosporidium scrofarum(n=39),Cryptosporidium parvum(n=4).Cryptosporidium suis and Cryptosporidium scrofarum were found in different age groups,Cryptosporidium parvum was only detected in nursery pigs and fattening pigs.The total infection rate of Giardia was 0.39 %(4/1039),with the highest infection rate of 1.34% in suckling piglets,1.04% in sows and 0.46% in nursery pigs.No Giardia infection was detected in fattening pigs.In different regions,only Baicheng City and Jilin City were detected Giardia infection,the infection rates were1.09% and 1.06%,respectively,Changchun City,Yanji City and Siping City were not detected Giardia infection;In different seasons,the infection rate was the highest in summer(8.45%),the lowest in spring(5.95%),and the infection rates in autumn and winter were 6.92% and 6.67%,respectively.The infection rate of Giardia in 2021 was7.87%,higher than 7.01% in 2022.The results of statistical analysis showed that there was no significant difference in the infection rate of Giardia in different regions,different years and different seasons(P > 0.05).Three genotypes were detected in this study,namely E(n=2),A(n=1)and B(n=1).The total infection rate of Blastocystis was 7.22%(75/1039),among which the highest infection rate was 8.33 % in nursery pigs,the lowest was 6.71% in suckling piglets,and the infection rates in finishing pigs and sows were 6.92% and 7.29%respectively.Among different regions,Baicheng had the highest infection rate of8.79%,Jilin had the lowest infection rate of 4.26%,Changchun,Yanji and Siping had the infection rates of 7.26%,6.35% and 6.54%,respectively.In different seasons,the highest infection rate was 8.45% in summer,the lowest infection rate was 5.95% in spring,and the infection rates in autumn and winter were 6.92% and 6.67%,respectively.Statistical analysis showed that there was no significant difference in the infection rate of Blastocystis in different regions,different years and different seasons(P > 0.05).Four subtypes of Blastocystis were detected in this study,ST1(n=2),ST3(n=19),ST5(n=48)and ST14(n=6).The total infection rate of Enterocytozoon bieneusi was 5.97%(62/1039),and the infection rate of sows was the highest(11.46%).The infection rate of suckling piglets was the lowest(4.03%).The infection rates of nursery pigs and fattening pigs were 4.63% and 6.06%,respectively.Among different regions,Changchun had the highest infection rate(7.71%).The lowest infection rate was 1.59% in Yanji City.The infection rates in Siping,Baicheng and Jilin were 7.14%,4.40% and 3.19%,respectively.Among the different seasons,the infection rate in autumn was the highest(6.92%).The lowest infection rate was 3.57% in spring.The infection rates in summer and winter were 6.08% and 4.58%,respectively.The infection rate of pigs in2022 was 6.24%,higher than 5.12% in 2021.The results of statistical analysis showed that there was no significant difference in the infection rate of Enterocytozoon bieneusi in different regions,different years and different seasons(P > 0.05).In this study,12 E.bieneusi genotypes were detected,namely CHG7(n = 1),CHN-DC1(n =1),CM11(n = 4),D(n = 6),Ebp A(n = 18),Ebp C(n = 14),G(n = 3),H(n = 6),JL1(n = 4),JL2(n = 2),JL3(n = 2),NCF7(n = 1).In this study,molecular biology methods were used to investigate the infection,species and genotype distribution of four intestinal protozoa in pigs in Jilin Province,China.The results showed that the total infection rate of intestinal protozoa in pigs in Jilin Province was 20.02%(208/1039),and the dominant species was Blastocystis(7.22%,75/1039).The results provide a scientific basis for further research on the four intestinal protozoa in Jilin Province,and provide a reference for the epidemiological investigation of parasites in China.