{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,7]],"date-time":"2026-07-07T00:36:09Z","timestamp":1783384569716,"version":"3.54.6"},"reference-count":28,"publisher":"American Veterinary Medical Association (AVMA)","issue":"11","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["javma"],"published-print":{"date-parts":[[2011,6,1]]},"abstract":"<jats:title>Abstract<\/jats:title>\n<jats:p><jats:bold>Objective<\/jats:bold>\u2014To assess the serial use of serum immunoperoxidase monolayer assays (IPMAs) and fecal PCR assays, combined with other diagnostic methods, to identify subclinical <jats:italic>Lawsonia intracellularis<\/jats:italic> infections for targeted treatment of Thoroughbred foals and weanlings at farms in which the pathogen was endemic or nonendemic.<\/jats:p>\n<jats:p><jats:bold>Design<\/jats:bold>\u2014Evaluation study.<\/jats:p>\n<jats:p><jats:bold>Animals<\/jats:bold>\u2014100 foals and weanlings (53 and 47 at farms in which <jats:italic>L intracellularis<\/jats:italic> was endemic and nonendemic, respectively).<\/jats:p>\n<jats:p><jats:bold>Procedures<\/jats:bold>\u2014Serum was collected every 4 weeks and tested via IPMA, for antibodies against <jats:italic>L intracellularis.<\/jats:italic> Fecal samples were collected every 2 weeks and tested by use of an <jats:italic>L intracellularis<\/jats:italic>\u2013specific PCR assay. When results for IPMAs or PCR assays were positive or clinical signs compatible with equine proliferative enteropathy (EPE) were detected, clinicopathologic testing was performed to determine treatment.<\/jats:p>\n<jats:p><jats:bold>Results<\/jats:bold>\u2014No foals had positive results for the <jats:italic>L intracellularis<\/jats:italic>\u2013specific IPMA until after weaning; 32 of 53 (60.4%) weanlings at the farm in which <jats:italic>L intracellularis<\/jats:italic> was endemic and 8 of 47 (170%) at the farm in which <jats:italic>L intracellularis<\/jats:italic> was nonendemic had positive IPMA results, whereas the number of weanlings that tested positive via fecal PCR assays at those farms was 6 and 0, respectively. Nineteen of 32 weanlings with positive IPMA results at the farm in which <jats:italic>L intracellularis<\/jats:italic> was endemic were treated for EPE; 5 of these had clinical signs of EPE. No weanlings at the nonendemic farm had clinical signs of or were treated for EPE.<\/jats:p>\n<jats:p><jats:bold>Conclusions and Clinical Relevance<\/jats:bold>\u2014IPMA appeared to be a useful means of identifying weanlings exposed to <jats:italic>L intracellularis.<\/jats:italic><\/jats:p>","DOI":"10.2460\/javma.238.11.1482","type":"journal-article","created":{"date-parts":[[2011,6,1]],"date-time":"2011-06-01T07:51:37Z","timestamp":1306914697000},"page":"1482-1489","source":"Crossref","is-referenced-by-count":23,"title":["Serial use of serologic assays and fecal PCR assays to aid in identification of subclinical Lawsonia intracellularis infection for targeted treatment of Thoroughbred foals and weanlings"],"prefix":"10.2460","volume":"238","author":[{"given":"Allen E.","family":"Page","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nathan M.","family":"Slovis","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Connie J.","family":"Gebhart","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Karen","family":"Wolfsdorf","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Samantha M.","family":"Mapes","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nicola","family":"Pusterla","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1272","reference":[{"key":"ref1","series-title":"J Comp Pathol","first-page":"77","article-title":"Proliferative enteropathy","volume":"122","author":"Lawson","year":"2000"},{"key":"ref2","series-title":"Vet Microbiol","first-page":"331","article-title":"Lawsonia intracellularis: getting inside the pathogenesis of proliferative 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Swine Health Prod","first-page":"211","article-title":"Studies on the ex vivo survival of","volume":"8","author":"Collins","year":"2000"}],"container-title":["Journal of the American Veterinary Medical Association"],"original-title":[],"link":[{"URL":"https:\/\/avmajournals.avma.org\/view\/journals\/javma\/238\/11\/javma.238.11.1482.xml","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/avmajournals.avma.org\/downloadpdf\/journals\/javma\/238\/11\/javma.238.11.1482.xml","content-type":"text\/html","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/avmajournals.avma.org\/downloadpdf\/journals\/javma\/238\/11\/javma.238.11.1482.xml","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,3,7]],"date-time":"2025-03-07T13:16:24Z","timestamp":1741353384000},"score":1,"resource":{"primary":{"URL":"https:\/\/avmajournals.avma.org\/view\/journals\/javma\/238\/11\/javma.238.11.1482.xml"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2011,6,1]]},"references-count":28,"journal-issue":{"issue":"11"},"URL":"https:\/\/doi.org\/10.2460\/javma.238.11.1482","relation":{},"ISSN":["0003-1488"],"issn-type":[{"value":"0003-1488","type":"print"}],"subject":[],"published":{"date-parts":[[2011,6,1]]}}}