First molecular characterization of Sarcocystis tenella in Tatra chamois (Rupicapra rupicapra tatrica) in Poland.

In this study, sarcocysts from three Polish Tatra chamois were isolated and identified using morphological and molecular methods for the first time. Six cysts were found in the latissimus dorsi muscle and another two in the diaphragm. No sarcocysts were detected in the myocardium, tongue, and esophagus. The isolated cysts were long with rounded ends, 0.35-0.61 mm in length, and 0.02-0.06 mm in width. All the sarcocysts were identified as Sarcocystis tenella on the basis of light microscopy and sequencing of cytochrome C oxidase subunit I (cox1) and small-subunit rRNA (ssu rRNA) genes. Comparative analysis showed a 99.23% identity of the cox1 gene sequences from Tatra chamois and sheep sarcocysts, and an even higher degree of sequence identity (99.88%) was documented in the case of the ssu rRNA gene. When compared at a haplotype level, all the sheep sequences of cox1 differed from those isolated from Tatra chamois. In contrast, one out of the two ssu rRNA haplotypes from the sheep isolates was identical with the haplotype from Tatra chamois. In conclusion, we showed that cox1 and ssu rRNA genes can be used as genetic markers for identification of the S. tenella, with cox1 gene providing better resolution during phylogenetic analyses. However, both genetic population analysis and phylogenetic inference with cox1 and ssu rRNA genes demonstrated that they do not constitute good markers for spatial differentiation of S. tenella.