Isolation,Identification And Detection Of Drug Resistance In Two Strains Of Eimeria Tenella

Coccidiosis is a pathogenic intestinal disease caused by different species of Eimeria spp.coccidia that causes dysentery,bloody stools,mental atrophy,and even death in chickens,causing significant economic losses to the livestock and poultry industries.Coccidiosis is widespread throughout the world,with regional variations in coccidial infection.Drug resistance in chickens is currently widespread and serious,and researchers both at home and abroad have devoted themselves to studying the mechanisms of drug resistance,developing new drugs,and developing new vaccines in order to find effective methods to prevent and control chicken coccidiosis.Scholars’ attention has recently shifted to the study of genetic levels and isoenzymes.These studies,however,require the use of single species,genotypically pure coccidia oocysts.To begin,single oocyst isolation and purification techniques were used in this study,and two Eimeria tenella strains were finally obtained in Hubei by morphological and PCR identification,named Et2 and Et8,respectively.In a chicken cage test,the biological characteristics of the two strains were investigated,including the shortest latent period,shortest sporulation time,and pathogenicity.The Et2 strain has a minimum latent period of129 hours and a minimum sporulation time of 16 hours,according to the results.It is highly pathogenic and is determined to be a virulent strain.The minimum latent period for the Et8 strain is 143 hours,and the minimum sporulation time is 18 hours.Its pathogenicity is weak,and it is determined as a weak strain.The anticoccidial index(ACI)was used as the primary indicator to evaluate the sensitivity of the two strains to the six anticoccidials,Monensin,Diclazuril,Halofuginone,Sulphasalazine sodium,Decoquinate,and Toltrazuril.The findings revealed that both Et2 and Et8 strains were susceptible to Decoquinate and,to variable levels,resistant to the other five anticoccidial drugs.Finally,the relatives of this geographical strain were examined using ITS-1 sequences and genetically compared with the reference genome using whole-genome resequencing techniques to determine differences.In terms of ITS-1 sequence sequencing,the Et2 strain is consistent with the Et8 strain,a co-ancestor with the Australian Eimeria tenella Houghton strain(AF446075.1),and more closely related to the Shanghai strain(FJ449692.1).For the two strains,the whole genome resequencing results were filtered to obtain data on single nucleotide polymorphism(SNP),small fragment insertion and deletion(In Del),structural variation(SV),and copy number variation(CNV).In this experiment,two Eimeria tenella strains from Hubei were successfully isolated and identified,and their biological characteristics,susceptibility to six anticoccidial drugs,kinship with other strains,and genomic-level variation were also identified.It provides more comprehensive information about the resistance mechanism of Eimeria spp,the development of new drugs,and the preparation of new vaccines and isoenzymes,and also provides some guidance for the use of anticoccidial drugs in the region.