{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,27]],"date-time":"2026-07-27T10:59:25Z","timestamp":1785149965211,"version":"3.55.0"},"reference-count":36,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2026,7,27]],"date-time":"2026-07-27T00:00:00Z","timestamp":1785110400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Animals"],"abstract":"<jats:p>Toxoplasma gondii is a cosmopolitan zoonotic parasite for which free-range poultry can act as sentinels of oocyst contamination. Romanian avian data on toxoplasmosis are limited to extensive systems and wildlife, while poultry seropositivity in intensive systems has not been previously characterized. In this study, 1940 domestic birds from intensive and extensive production systems were tested for T. gondii IgG antibodies by the Modified Agglutination Test (MAT). The descriptive dataset included data on 813 intensive broiler chickens and 1127 backyard birds. Backyard chickens had roughly twice the MAT seroprevalence of intensive broilers (31.2% vs. 14.1%, p &lt; 0.001), rising to more than a tenfold difference at \u22651:48 (18.7% vs. 1.7%, p &lt; 0.001). Seroprevalence varied among counties and farms, but intensive broilers were sampled in a very delimited area, so geographic and production-system patterns partly overlapped and should not be interpreted independently. In models adjusting for county and age, intensive production remained associated with lower odds of infection. These findings establish the first Romanian seroprevalence baseline for intensive poultry and support risk-based surveillance focused on backyard flocks and counties with high extensive-system prevalence.<\/jats:p>","DOI":"10.3390\/ani16152313","type":"journal-article","created":{"date-parts":[[2026,7,27]],"date-time":"2026-07-27T09:47:41Z","timestamp":1785145661000},"page":"2313","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Seroprevalence of Toxoplasma gondii in Poultry from Backyard and Intensive Production Systems in Romania"],"prefix":"10.3390","volume":"16","author":[{"given":"Maria","family":"Nedi\u0219an","sequence":"first","affiliation":[{"name":"Department of Parasitology and Parasitic Diseases, Faculty of Veterinary Medicine, University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca, 3-5 Calea M\u0103n\u0103\u015ftur Street, 400372 Cluj-Napoca, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6453-2370","authenticated-orcid":false,"given":"Adriana","family":"Gy\u00f6rke","sequence":"additional","affiliation":[{"name":"Department of Parasitology and Parasitic Diseases, Faculty of Veterinary Medicine, University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca, 3-5 Calea M\u0103n\u0103\u015ftur Street, 400372 Cluj-Napoca, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8527-2309","authenticated-orcid":false,"given":"Vlad-Dan","family":"Cotu\u021biu","sequence":"additional","affiliation":[{"name":"AINIMAL SRL, Strada Stejarului 41D, 407280 Flore\u0219ti, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0772-3343","authenticated-orcid":false,"given":"Mircea","family":"Coroian","sequence":"additional","affiliation":[{"name":"Department of Parasitology and Parasitic Diseases, Faculty of Veterinary Medicine, University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca, 3-5 Calea M\u0103n\u0103\u015ftur Street, 400372 Cluj-Napoca, Romania"},{"name":"Department of Poultry Management and Pathology, University of Agricultural Sciences and Veterinary Medicine of Cluj-Napoca, 400372 Cluj-Napoca, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Toma Naic","family":"Andra","sequence":"additional","affiliation":[{"name":"Department of Parasitology and Parasitic Diseases, Faculty of Veterinary Medicine, University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca, 3-5 Calea M\u0103n\u0103\u015ftur Street, 400372 Cluj-Napoca, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8587-3753","authenticated-orcid":false,"given":"Vasile","family":"Cozma","sequence":"additional","affiliation":[{"name":"Department of Parasitology and Parasitic Diseases, Faculty of Veterinary Medicine, University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca, 3-5 Calea M\u0103n\u0103\u015ftur Street, 400372 Cluj-Napoca, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Radu","family":"Blaga","sequence":"additional","affiliation":[{"name":"Anses, INRAE, Ecole Nationale V\u00e9t\u00e9rinaire d\u2019Alfort, Laboratoire de Sant\u00e9 Animale, BIPAR, 94700 Maisons-Alfort, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Amandine","family":"Blaizot","sequence":"additional","affiliation":[{"name":"Anses, INRAE, Ecole Nationale V\u00e9t\u00e9rinaire d\u2019Alfort, Laboratoire de Sant\u00e9 Animale, BIPAR, 94700 Maisons-Alfort, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7415-4198","authenticated-orcid":false,"given":"Isabelle","family":"Villena","sequence":"additional","affiliation":[{"name":"UR ESCAPE, Universit\u00e9 Champagne-Ardenne, 51100 Reims, France"},{"name":"Centre National de R\u00e9f\u00e9rence Toxoplasmose, Centre Hospitalier Universitaire, 51092 Reims, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5936-2538","authenticated-orcid":false,"given":"C\u0103lin","family":"Gherman","sequence":"additional","affiliation":[{"name":"Department of Parasitology and Parasitic Diseases, Faculty of Veterinary Medicine, University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca, 3-5 Calea M\u0103n\u0103\u015ftur Street, 400372 Cluj-Napoca, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,7,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Calero-Bernal, R., Fern\u00e1ndez-Escobar, M., Katzer, F., Su, C., and Ortega-Mora, L.M. 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