{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,24]],"date-time":"2026-02-24T06:53:47Z","timestamp":1771916027453,"version":"3.50.1"},"reference-count":21,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2021,4,30]],"date-time":"2021-04-30T00:00:00Z","timestamp":1619740800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Instituto Nacional de Tecnolog\u00eda Agropecuaria","award":["REs. No. 1177\/14"],"award-info":[{"award-number":["REs. No. 1177\/14"]}]},{"DOI":"10.13039\/100011310","name":"Rural and Environment Science and Analytical Services Division","doi-asserted-by":"publisher","award":["Strategic Research Programme, 2016\u20132021"],"award-info":[{"award-number":["Strategic Research Programme, 2016\u20132021"]}],"id":[{"id":"10.13039\/100011310","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pathogens"],"abstract":"<jats:p>Chlamydia abortus infects livestock species worldwide and is the cause of enzootic abortion of ewes (EAE). In Europe, control of the disease is achieved using a live vaccine based on C. abortus 1B strain. Although the vaccine has been useful for controlling disease outbreaks, abortion events due to the vaccine have been reported. Recently, placental pathology resulting from a vaccine type strain (vt) infection has been reported and shown to be similar to that resulting from a natural wild-type (wt) infection. The aim of this study was to extend these observations by comparing the distribution and severity of the lesions, the composition of the predominating cell infiltrate, the amount of bacteria present and the role of the blood supply in infection. A novel system for grading the histological and pathological features present was developed and the resulting multi-parameter data were statistically transformed for exploration and visualisation through a tailored principal component analysis (PCA) to evaluate the difference between them. The analysis provided no evidence of meaningful differences between vt and wt strains in terms of the measured pathological parameters. The study also contributes a novel methodology for analysing the progression of infection in the placenta for other abortifacient pathogens.<\/jats:p>","DOI":"10.3390\/pathogens10050543","type":"journal-article","created":{"date-parts":[[2021,4,30]],"date-time":"2021-04-30T10:53:29Z","timestamp":1619780009000},"page":"543","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Distribution and Severity of Placental Lesions Caused by the Chlamydia abortus 1B Vaccine Strain in Vaccinated Ewes"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5631-3557","authenticated-orcid":false,"given":"Sergio Gast\u00f3n","family":"Caspe","sequence":"first","affiliation":[{"name":"Moredun Research Institute, Edinburgh EH26 0PZ, UK"},{"name":"Royal (Dick) School of Veterinary Studies, University of Edinburgh, Edinburgh EH25 9RG, UK"},{"name":"Estaci\u00f3n Experimental Mercedes, Instituto Nacional de Tecnolog\u00eda Agropecuaria (INTA), Mercedes CP 3470, Argentina"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0162-669X","authenticated-orcid":false,"given":"Javier","family":"Palarea-Albaladejo","sequence":"additional","affiliation":[{"name":"Biomathematics and Statistics Scotland, Edinburgh EH9 3FDK, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Clare","family":"Underwood","sequence":"additional","affiliation":[{"name":"Moredun Research Institute, Edinburgh EH26 0PZ, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Morag","family":"Livingstone","sequence":"additional","affiliation":[{"name":"Moredun Research Institute, Edinburgh EH26 0PZ, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2218-5144","authenticated-orcid":false,"given":"Sean Ranjan","family":"Wattegedera","sequence":"additional","affiliation":[{"name":"Moredun Research Institute, Edinburgh EH26 0PZ, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Elspeth","family":"Milne","sequence":"additional","affiliation":[{"name":"Royal (Dick) School of Veterinary Studies, University of Edinburgh, Edinburgh EH25 9RG, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Neil Donald","family":"Sargison","sequence":"additional","affiliation":[{"name":"Royal (Dick) School of Veterinary Studies, University of Edinburgh, Edinburgh EH25 9RG, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9962-446X","authenticated-orcid":false,"given":"Francesca","family":"Chianini","sequence":"additional","affiliation":[{"name":"Moredun Research Institute, Edinburgh EH26 0PZ, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0086-8443","authenticated-orcid":false,"given":"David","family":"Longbottom","sequence":"additional","affiliation":[{"name":"Moredun Research Institute, Edinburgh EH26 0PZ, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,4,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"217","DOI":"10.1053\/jcpa.2002.0629","article-title":"Animal Chlamydioses and Zoonotic Implications","volume":"128","author":"Longbottom","year":"2003","journal-title":"J. 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