The Role of Mustelids in the Transmission of Sarcocystis spp. Using Cattle as Intermediate Hosts

SIMPLE SUMMARY: Members of the genus Sarcocystis are worldwide distributed protozoan parasites. Sarcocystis infections cause great losses in economically important animals. There is a lack of studies on Sarcocystis in naturally infected wild predators, especially of the family Mustelidae which represent a presumably important group of definitive hosts of these parasites. The objective of the present study was to examine the small intestine samples of various mustelid species from Lithuania serving as a possible source of Sarcocystis spp. using cattle as intermediate hosts. Overall, 84 samples collected from five mustelid species were analyzed. Oocysts/sporocysts of Sarcocystis spp. were detected in 75 animals (89.3%). Using molecular methods four Sarcocystis spp., S. bovifelis, S. cruzi, S. hirsuta and S. hominis were identified, with the first two being the most prevalent. These results indicate that mustelids are involved in the transmission of Sarcocystis spp. using cattle as intermediate hosts. The determined high prevalence of Sarcocystis spp. rates cause concerns about food safety issues. To control the spread of infection, further studies on the way carcasses of cattle or beef waste become accessible to mustelids are needed. ABSTRACT: There is a lack of research on the role of mustelids in the transmission of various Sarcocystis spp. In the present study we tested the hypothesis that widespread mustelids in Lithuania could be involved in the transmission of Sarcocystis spp. using cattle as intermediate hosts. In 2016–2020, intestinal samples of 84 mustelids were examined. Sarcocystis spp. were identified by species-specific PCR targeting the cox1 gene and subsequent sequencing. Under a light microscope, oocysts/sporocysts of Sarcocystis spp. were observed in 40 samples (47.6%), while using molecular methods, they were detected in 75 animals (89.3%). Four Sarcocystis spp. were identified in the intestinal samples of American mink (Neovison vison), Beech marten (Martes foina), European pine marten (Martes martes), European badger (Meles meles) and European polecat (Mustela putorius). The prevalence of predominant Sarcocystis spp., S. bovifelis (89.3%) and S. cruzi (73.8%) was significantly higher than that of S. hirsuta (3.6%) and S. hominis (1.2%). In an individual sample, most frequently two Sarcocystis spp. were identified (69.0%), then a single species (15.5%) and three species (4.8%). The present study provides strong evidence that mustelids serve as definitive hosts for Sarcocystis spp. using cattle as intermediate hosts.