{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,1]],"date-time":"2026-10-01T17:04:13Z","timestamp":1790874253481,"version":"4.1.0"},"reference-count":23,"publisher":"American Veterinary Medical Association (AVMA)","issue":"10","license":[{"start":{"date-parts":[[2026,10,1]],"date-time":"2026-10-01T00:00:00Z","timestamp":1790812800000},"content-version":"unspecified","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["ajvr"],"published-print":{"date-parts":[[2026,10,1]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec id=\"sc_a1\">\n                    <jats:title>Objective<\/jats:title>\n                    <jats:p>To evaluate formiminoglutamic acid (FIGLU) as a potential marker of folate deficiency in cats and dogs by (1) establishing a liquid chromatography\u2013tandem mass spectrometry (LC-MS-MS) method for the quantification of FIGLU in feline and canine plasma, and (2) reporting plasma FIGLU concentrations in clinically normal cats and dogs.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sc_a2\">\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>An LC-MS-MS method for FIGLU quantitation was developed and analytically validated. Clinically normal cats and dogs were prospectively included for plasma FIGLU and serum folate measurement (via LC-MS-MS and chemiluminescence immunoassay, respectively). Statistical analysis was performed to assess for correlations between plasma FIGLU and serum folate concentrations.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sc_a3\">\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Accuracy, precision, linearity, and recovery experiments met validation requirements. Dilution integrity experiments did not meet the acceptance criteria, potentially due to ion suppression effects. Plasma FIGLU ranged from 4.5 to 21.0 ng\/mL in 11 clinically normal dogs and 9.1 to 57.0 ng\/mL in 10 clinically normal cats. There was no evidence of a correlation between serum folate and plasma FIGLU concentrations in clinically normal cats and dogs.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sc_a4\">\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>The amount of FIGLU present in the plasma of clinically normal cats and dogs is quantifiable via LC-MS-MS, and reference interval determination of plasma FIGLU is therefore feasible. Future studies should include both normofolatemic and hypofolatemic animals to assess the correlation between serum folate and plasma FIGLU and to determine the optimal serum folate cutoff limit.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sc_a5\">\n                    <jats:title>Clinical Relevance<\/jats:title>\n                    <jats:p>Plasma FIGLU shows promise as a practical research tool and a potential functional marker of folate availability in cats and dogs.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.2460\/ajvr.26.03.0112","type":"journal-article","created":{"date-parts":[[2026,7,1]],"date-time":"2026-07-01T12:47:17Z","timestamp":1782910037000},"source":"Crossref","is-referenced-by-count":0,"title":["Plasma formiminoglutamic acid shows potential as a functional marker of folate deficiency in cats and dogs: development and validation of a liquid chromatography\u2013tandem mass spectrometry method"],"prefix":"10.2460","volume":"87","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1833-5322","authenticated-orcid":true,"given":"Margaret","family":"Cohn-Urbach","sequence":"first","affiliation":[{"name":"Sydney School of Veterinary Science, Faculty of Science, The University of Sydney, Sydney, NSW, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Craig G.","family":"Ruaux","sequence":"additional","affiliation":[{"name":"Sydney School of Veterinary Science, Faculty of Science, The University of Sydney, Sydney, NSW, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1272","reference":[{"issue":"1","key":"B1","series-title":"Tierarztl Prax Ausg K Kleintiere Heimtiere","first-page":"15","article-title":"Correlation of clinical, diagnostic and histopathological parameters in dogs with chronic lymphocytic-plasmacytic enteropathy","volume":"46","author":"Moser K","year":"2018","unstructured":"Moser K, Mitze S, Teske E, von Bomhard W, Stockhaus C. 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