First Detection and Molecular Characterization of Entamoeba spp. in Pet Mongolian Gerbils (Meriones unguiculatus) and Fat-Tailed Gerbils (Pachyuromys duprasi) in China.

PURPOSE: Entamoeba spp. are anaerobic protists primarily inhabiting vertebrate digestive tracts, some of which are pathogenic or zoonotic. However, genetic information on Entamoeba spp. in rodents, including gerbils, is scarce. This study aimed to investigate the prevalence and molecular characterization of Entamoeba in two pet gerbil species in China.

METHODS

A total of 120 fecal samples were collected from pet Mongolian gerbils and fat-tailed gerbils (60 each) purchased from six pet shops in three provinces. Microscopy, PCR, and sequence analysis of small subunit ribosomal RNA (SSU rRNA) gene were used for detection and identification.

RESULTS

The overall Entamoeba infection rate was 10.0%, with 11.7% (7/60) in Mongolian gerbils and 8.3% (5/60) in fat-tailed gerbils. Sequence and phylogenetic analyses identified E. muris (n = 10) and a novel conditional lineage designated Entamoeba CL-FTG (n = 2). Three E. muris sequence types were detected (88.6%-100% similarity), all closely related to the reference sequence AB445018 from a Mongolian gerbil, with 90.02% to 100% similarities. Entamoeba CL-FTG from two fat-tailed gerbils was most closely related to Entamoeba RL11 from a field vole, with 86.44% similarity. Cysts of E. muris from both gerbil species were morphologically similar, differing only slightly in size. No zoonotic E. histolytica/E. dispar DNA was detected.

CONCLUSION

This study provides the first molecular characterization of eight-nucleated Entamoeba in pet gerbils in China and the first report of E. muris cysts and their partial SSU rDNA sequences from fat-tailed gerbils, enriching our understanding of Entamoeba genetic diversity.