Identification And Establishment Of Fluorescent Quantitative PCR Detection Method Of Candida Albicans

The incidence of candidiasis chicken rate showed an upward trend,its harm is more and more big.The diagnosis of chicken candidiasis mainly depends on clinical symptoms and pathological examination,these methods are low sensitivity,poor specificity,time-consuming,and can’t make accurate diagnosis in time,so as to affect the early diagnosis and early treatment of the disease.Therefore,the study of rapid detection of candida albicans has important significance for differential diagnosis and epidemiological investigation of candida albicans.For the separation and identification of suspected candida albicans,from diseased chicken crop isolated 5 strains by chromogenic medium,germ tube formation,chlamydospore induction and ITS gene comparison and typing test.The results showed that the isolate was on potato medium,the colony was round,milky white,and the back was not pigmentation,under the microscope,both by toluidine blue staining or fluorescence staining,the size of thallus is different,as the yeast like fungus round or oval shaped,gram stain positive,under the Chromogenic medium,Candida albicans is colorless,other Candida red,formation of germ tube in serum medium,thick spore derived from corn flour Twain medium,IST gene sequence analysis,the homology of the isolates was 96.9 ~ 97.4%,and the homology with GenBank while Candida albicans was divided into 97.4%,the homology with other Candida was 94.6 ~ 76.92%.Gene typing was A and C type.Combined with morphological characteristics and gene homology analysis,the isolate was identified as candida albicans.A pair of primers with length of 273 bp was designed according to the nucleotide sequence of internal transcribed intergenic domain of candida albicans rDNA published by GenBank,using LightCycler real time PCR detection method,using SYBR Green I as the fluorescent stain of amplified products,the blood samples of suspected cases of avian candida albicans were detected,and the specificity of the method was tested with 5 common pathogenic fungi.The detection method of chicken candida albicans has high sensitivity,and the minimum detectable concentration of candida albicans is 101 CFU/mL,strong specificity,no cross reaction with candida,candida,candida tropicalis,candida tropicalis,aspergillus fumigatus and other pathogenic fungi,short time,just two hours to complete the entire test process.