{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,5]],"date-time":"2026-04-05T04:20:48Z","timestamp":1775362848547,"version":"3.50.1"},"reference-count":27,"publisher":"Oxford University Press (OUP)","issue":"5","license":[{"start":{"date-parts":[[2026,2,19]],"date-time":"2026-02-19T00:00:00Z","timestamp":1771459200000},"content-version":"vor","delay-in-days":171,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc-nd\/4.0\/"},{"start":{"date-parts":[[2025,8,27]],"date-time":"2025-08-27T00:00:00Z","timestamp":1756252800000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by-nc-nd\/4.0\/"}],"funder":[{"name":"The Seed for International Activities Program, sponsored by Global Affairs at UCD","award":["PD1001"],"award-info":[{"award-number":["PD1001"]}]},{"name":"Gifts from anonymous donors towards the Equine and Comparative Neurology Research Group","award":["V435AM2"],"award-info":[{"award-number":["V435AM2"]}]}],"content-domain":{"domain":["onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2025,9,1]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Long-term freezing storage can alter the stability of proteins, thereby compromising accurate determination of indirect fluorescent antibody test (IFAT) titers that support the diagnosis of equine protozoal myeloencephalitis.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Objective<\/jats:title>\n                    <jats:p>Assess the effect of long-term storage at \u221280\u00b0C on IFAT against S. neurona and N. hughesi in equine serum and cerebrospinal fluid (CSF).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Samples<\/jats:title>\n                    <jats:p>Paired serum and CSF (n\u2009=\u200946), and serum only (n\u2009=\u200925) samples.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>Prospective study of samples stored 6\u201312, 13\u201318, and 19\u201324\u2009months. Comparing antibody titers across time points, McNemar and Wilcoxon rank tests were used for statistical analysis.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>After long-term freezing storage for 19\u201324\u2009months, N. hughesi IFAT results for CSF were significantly different compared with their fresh-testing time point (p\u2009=\u20090.04), but a similar difference was not observed for serum samples. No statistical differences were observed for serum or CSF samples tested for S. neurona after 6\u201312, 13\u201318, or 19\u201324\u2009months compared with their original fresh testing results. However, the serum to CSF ratio cutoff of \u2264\u200964 in support of disease changed in 41% (19 of 46) of paired samples.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions and Clinical Importance<\/jats:title>\n                    <jats:p>Freezing samples at \u221280\u00b0C for more than 18\u2009months might alter test results, leading to possible changes in serum to CSF ratio calculations and affecting the interpretation of results for clinical and research purposes.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1111\/jvim.70225","type":"journal-article","created":{"date-parts":[[2025,8,28]],"date-time":"2025-08-28T06:50:59Z","timestamp":1756363859000},"update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Effect of Long-Term Freezing on Indirect Fluorescent Antibody Titers for the Diagnosis of Equine Protozoal Myeloencephalitis"],"prefix":"10.1093","volume":"39","author":[{"given":"Claudia","family":"Valderrama-Martinez","sequence":"first","affiliation":[{"name":"Departamento de Salud Animal, Facultad de Medicina Veterinaria y Zootecnia. Universidad Nacional de Colombia , Bogot\u00e1,","place":["Colombia"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Andrea","family":"Packham","sequence":"additional","affiliation":[{"name":"One Health Institute, School of Veterinary Medicine, University of California Davis , Davis, California,","place":["USA"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Woutrina","family":"Smith","sequence":"additional","affiliation":[{"name":"One Health Institute, School of Veterinary Medicine, University of California Davis , Davis, California,","place":["USA"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jorge Eduardo","family":"Mendoza-Flores","sequence":"additional","affiliation":[{"name":"School of Veterinary Medicine, University of California Davis Department of Medicine and Epidemiology, , Davis, California,","place":["USA"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Shichen","family":"Zheng","sequence":"additional","affiliation":[{"name":"School of Veterinary Medicine, University of California Davis Department of Medicine and Epidemiology, , Davis, California,","place":["USA"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6841-2448","authenticated-orcid":false,"given":"Munashe","family":"Chigerwe","sequence":"additional","affiliation":[{"name":"School of Veterinary Medicine, University of California Davis Department of Medicine and Epidemiology, , Davis, California,","place":["USA"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Magdalena","family":"Plancarte","sequence":"additional","affiliation":[{"name":"One Health Institute, School of Veterinary Medicine, University of California Davis , Davis, California,","place":["USA"]},{"name":"Karen C. 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