{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,5]],"date-time":"2025-12-05T05:27:25Z","timestamp":1764912445197,"version":"3.46.0"},"reference-count":35,"publisher":"MDPI AG","issue":"23","license":[{"start":{"date-parts":[[2025,12,2]],"date-time":"2025-12-02T00:00:00Z","timestamp":1764633600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","award":["2021.09461.BD","2025.04664.BD"],"award-info":[{"award-number":["2021.09461.BD","2025.04664.BD"]}]},{"name":"FCT"},{"name":"Science and Technology Foundation","award":["GHTM-UID\/04413\/2020","LA-REAL LA\/P\/0117\/2020","CERNAS UIDB\/00681\/2020"],"award-info":[{"award-number":["GHTM-UID\/04413\/2020","LA-REAL LA\/P\/0117\/2020","CERNAS UIDB\/00681\/2020"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Animals"],"abstract":"<jats:p>Sarcocystis spp. are cyst-forming protozoan parasites with a global distribution that infect a wide range of domestic and wild animals, impacting both animal health and livestock productivity. In sheep, infections can cause clinical disease, reproductive losses, and economic damage, particularly when pathogenic species such as Sarcocystis tenella are involved. Grazing sheep, including breeds such as the Serra da Estrela from central Portugal, are at increased risk due to frequent contact with shepherd dogs, which serve as definitive hosts. Despite their significance, data on the occurrence and distribution of Sarcocystis spp. in Portuguese sheep remain limited. This study analyzed 179 samples collected in central Portugal during 2024, including 41 brain tissues and 88 blood samples from sheep, and 50 stool samples from shepherd dogs, using conventional PCR and bidirectional Sanger sequencing. Sarcocystis sp. closely related to S. tenella was detected exclusively in sheep brain tissue, with a prevalence of 4.9% (2\/41; 95% CI: 0.60\u201316.53), while no parasite DNA was found in blood or dog samples. These results provide the first molecular confirmation of Sarcocystis spp. closely related to S. tenella in Portuguese sheep raised for human consumption and establish baseline data for future epidemiological surveillance and control strategies.<\/jats:p>","DOI":"10.3390\/ani15233479","type":"journal-article","created":{"date-parts":[[2025,12,3]],"date-time":"2025-12-03T08:44:28Z","timestamp":1764751468000},"page":"3479","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Molecular Screening of Sarcocystis spp. in Grazing Sheep (Ovis aries) and Shepherd Dogs (Canis lupus familiaris) from Central Portugal"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8374-3739","authenticated-orcid":false,"given":"Sara","family":"Gomes-Gon\u00e7alves","sequence":"first","affiliation":[{"name":"School of Medicine and Biomedical Sciences (ICBAS), Universidade do Porto (UP), 4050-313 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0009-0006-9626-321X","authenticated-orcid":false,"given":"Ricardo J.","family":"Figueiredo","sequence":"additional","affiliation":[{"name":"School of Medicine and Biomedical Sciences (ICBAS), Universidade do Porto (UP), 4050-313 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-2191-9831","authenticated-orcid":false,"given":"Soraia","family":"Rodrigues","sequence":"additional","affiliation":[{"name":"School of Medicine and Biomedical Sciences (ICBAS), Universidade do Porto (UP), 4050-313 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0009-0003-1324-8902","authenticated-orcid":false,"given":"Jaqueline T.","family":"Bento","sequence":"additional","affiliation":[{"name":"School of Medicine and Biomedical Sciences (ICBAS), Universidade do Porto (UP), 4050-313 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9742-5643","authenticated-orcid":false,"given":"S\u00e9rgio","family":"Santos-Silva","sequence":"additional","affiliation":[{"name":"School of Medicine and Biomedical Sciences (ICBAS), Universidade do Porto (UP), 4050-313 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0872-4954","authenticated-orcid":false,"given":"Daniela","family":"Almeida","sequence":"additional","affiliation":[{"name":"School of Medicine and Biomedical Sciences (ICBAS), Universidade do Porto (UP), 4050-313 Porto, Portugal"}]},{"given":"Rita","family":"Cruz","sequence":"additional","affiliation":[{"name":"Escola Superior Agr\u00e1ria de Viseu, Instituto Polit\u00e9cnico de Viseu, 3504-510 Viseu, Portugal"},{"name":"Epidemiology Research Unit (EPIUnit), Instituto de Sa\u00fade P\u00fablica da Universidade do Porto, 4050-091 Porto, Portugal"},{"name":"Laborat\u00f3rio para a Investiga\u00e7\u00e3o Integrativa e Translacional em Sa\u00fade Populacional (ITR), 4050-600 Porto, Portugal"}]},{"given":"Fernando","family":"Esteves","sequence":"additional","affiliation":[{"name":"Escola Superior Agr\u00e1ria de Viseu, Instituto Polit\u00e9cnico de Viseu, 3504-510 Viseu, Portugal"},{"name":"CERNAS-IPV Research Centre, Instituto Polit\u00e9cnico de Viseu, 3504-510 Viseu, Portugal"}]},{"given":"Alexandra Lameira","family":"Baptista","sequence":"additional","affiliation":[{"name":"Escola Superior Agr\u00e1ria de Viseu, Instituto Polit\u00e9cnico de Viseu, 3504-510 Viseu, Portugal"},{"name":"CERNAS-IPV Research Centre, Instituto Polit\u00e9cnico de Viseu, 3504-510 Viseu, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4054-9124","authenticated-orcid":false,"given":"Maria Aires","family":"Pereira","sequence":"additional","affiliation":[{"name":"Escola Superior Agr\u00e1ria de Viseu, Instituto Polit\u00e9cnico de Viseu, 3504-510 Viseu, Portugal"},{"name":"CERNAS-IPV Research Centre, Instituto Polit\u00e9cnico de Viseu, 3504-510 Viseu, Portugal"},{"name":"Global Health and Tropical Medicine (GHTM), Associate Laboratory in Translation and Innovation Towards Global Health (LA-REAL), Instituto de Higiene e Medicina Tropical (IHMT), Universidade NOVA de Lisboa (UNL), 1349-008 Lisboa, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6145-7560","authenticated-orcid":false,"given":"Lu\u00eds","family":"Cardoso","sequence":"additional","affiliation":[{"name":"Department of Veterinary Sciences, Universidade de Tr\u00e1s-os-Montes e Alto Douro (UTAD), Quinta de Prados, 5000-801 Vila Real, Portugal"},{"name":"Department of Veterinary Sciences and Animal and Veterinary Research Centre (CECAV), Universidade de Tr\u00e1s-os-Montes e Alto Douro (UTAD), Quinta de Prados, 5000-801 Vila Real, Portugal"},{"name":"Associate Laboratory for Animal and Veterinary Science (AL4AnimalS), 1300-477 Lisboa, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8769-8103","authenticated-orcid":false,"given":"Jo\u00e3o R.","family":"Mesquita","sequence":"additional","affiliation":[{"name":"School of Medicine and Biomedical Sciences (ICBAS), Universidade do Porto (UP), 4050-313 Porto, Portugal"},{"name":"Associate Laboratory for Animal and Veterinary Science (AL4AnimalS), 1300-477 Lisboa, Portugal"},{"name":"Centro de Estudos de Ci\u00eancia Animal (CECA), Instituto de Ci\u00eancias, Tecnologias e Agroambiente (ICETA), Universidade do Porto (UP), 4051-401 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2025,12,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"5562517","DOI":"10.1155\/2021\/5562517","article-title":"Molecular and Microscopic Investigation of Sarcocystis Species Isolated from Sheep Muscles in Iran","volume":"2021","author":"Pestechian","year":"2021","journal-title":"J. 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