Molecular detection and zoonotic genotyping of Enterocytozoon bieneusi in Siberian tigers (Panthera tigris altaica), Northeast China

Enterocytozoon bieneusi is an important zoonotic pathogen. This study examined its prevalence and genotypes in Siberian tigers in Northeast China. Fecal samples from 97 captive and 5 wild tigers were analyzed by nested PCR targeting the ITS region. Prevalence in captive tigers was 40.2% (39/97), with no significant site differences. Three genotypes were identified: D (89.7%), Peru8 (7.7%), and Type IV (2.6%), all within zoonotic Group 1. E. bieneusi was detected for the first time in a wild Siberian tiger (genotype D). The predominance of genotype D-common in poultry-suggests dietary transmission through contaminated chicken meat. These results indicate high prevalence of zoonotic genotypes in tigers, underscoring cross-species transmission risks and the need for strengthened biosecurity and surveillance.