Introduction and objective:
Free-living small rodents and insectivores are an important part of the diet of many species of carnivores and omnivores, contributing to the spread of T. gondii infections in the environment. The aim of the study was to assess the occurrence of T. gondii infection in the free-living small mammals population from the Lublin Province, and to determine their potential importance in spreading this invasion in the environment. The research was based on the detection and analysis of the parasite DNA isolated from tissue samples.

Material and methods:
Sixty dead, small mammals from the Lublin Province, belonging to 7 species were collected. DNA from animal tissue samples was isolated using a commercial kit (QIAGEN). Tests for the presence of T. gondii DNA were performed by nested and Real-time PCR based on the amplification of the B1 fragment gene. To determine the clonal type of the parasite, selected DNA isolates were tested by RFLP PCR with 12 genetic markers. The amplification products of selected samples were subjected to sequencing and phylogenetic analysis.

Overall, among 180 tissue samples from 60 small mammals tested in nested and/or Real time PCR, T. gondii DNA was found in samples from 10 rodents (16.7%). RFLP-PCR and sequence analysis revealed the presence of T. gondii clonal types II and III in the majority of the tested samples.

The results of study indicate a high degree of T. gondii infection in free-living small mammals (especially rodents) from the Lublin Province (16.7%), and confirm the important role of these animals as a reservoir and vector of the parasite in the environment.

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