{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,11,5]],"date-time":"2026-11-05T08:29:26Z","timestamp":1793867366808,"version":"4.6.1"},"reference-count":43,"publisher":"SAGE Publications","issue":"11","license":[{"start":{"date-parts":[[2026,8,11]],"date-time":"2026-08-11T00:00:00Z","timestamp":1786406400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"},{"start":{"date-parts":[[2026,8,11]],"date-time":"2026-08-11T00:00:00Z","timestamp":1786406400000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/journals.sagepub.com\/page\/policies\/text-and-data-mining-license"}],"funder":[{"name":"IVC evidensia","id":[{"id":"https:\/\/ror.org\/002cx2f43","id-type":"ROR","asserted-by":"crossref"}]}],"content-domain":{"domain":["journals.sagepub.com"],"crossmark-restriction":true},"short-container-title":["Journal of Feline Medicine and Surgery"],"published-print":{"date-parts":[[2026,11]]},"abstract":"<jats:sec>\n                    <jats:title>Objectives:<\/jats:title>\n                    <jats:p>The aim of the present study was to investigate the prevalence of hypo- and hypercobalaminaemia in a cohort of cats with diverse disease pathologies and to assess associations with signalment and disease characteristics.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods:<\/jats:title>\n                    <jats:p>Residual blood from cats presented to a large veterinary referral hospital during a 24-month period was used for serum B12 quantification. All cats requiring blood collection as part of diagnostic investigations were eligible for inclusion regardless of clinical presentation. Serum B12 concentration was assessed according to signalment, body weight, body condition score, primary affected body system and type of disease pathology as derived from the clinical notes.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results:<\/jats:title>\n                    <jats:p>A total of 229 cats were enrolled:\u2009128 male\u2009(119 neutered, 9 entire) and\u2009101 female\u2009(88 neutered, 13 entire).\u2009Of these, 176 were domestic shorthair or longhair, and 53 were purebred. The median age was 9.9 years and median body weight 4.1\u2009kg. Of the 229 cats, 80 (34.9%) had high serum B12, 86 (37.6%) had normal, 18 (7.9%) had borderline and 45 (19.7%) had low serum B12. Median serum B12 concentration was higher in cats aged &lt;8.0 years than \u2a7e8.0 years, and there was a\u2009weak but significant\u2009negative correlation between age and serum B12. Median serum B12 concentration was lower in cats weighing &lt;3.0\u2009kg than in those \u2a7e3.0\u2009kg, and a\u2009weak but significant\u2009positive correlation was found between body weight and serum B12 concentration. No associations were found between serum B12 and sex, breed, body condition score, affected body system or pathology type.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions and relevance:<\/jats:title>\n                    <jats:p>Vitamin B12 aberrations were common in this cohort of cats, with approximately one-third and one-fifth having abnormally high and low serum concentrations, respectively. Serum vitamin B12 concentration declined with advancing age, and hypocobalaminaemia was more prevalent in cats with body weights &lt;3.0\u2009kg. Hypo- and hypercobalaminaemia were documented in cats with a wide variety of clinical presentations, and no specific disease associations were elucidated.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1177\/1098612x261478796","type":"journal-article","created":{"date-parts":[[2026,8,12]],"date-time":"2026-08-12T04:03:56Z","timestamp":1786507436000},"update-policy":"https:\/\/doi.org\/10.1177\/sage-journals-update-policy","source":"Crossref","is-referenced-by-count":0,"title":["Prevalence and clinical relevance of hypocobalaminaemia and hypercobalaminaemia in cats"],"prefix":"10.1177","volume":"28","author":[{"ORCID":"https:\/\/orcid.org\/0009-0007-4265-8248","authenticated-orcid":false,"given":"Clara","family":"Casas","sequence":"first","affiliation":[{"name":"Pride Veterinary Referrals, Derby, UK"},{"name":"Dovecote Veterinary Referrals, Castle Donington, Derby, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Charlotte","family":"Dye","sequence":"additional","affiliation":[{"name":"Pride Veterinary Referrals, Derby, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"179","published-online":{"date-parts":[[2026,8,11]]},"reference":[{"key":"e_1_3_3_2_2","doi-asserted-by":"crossref","unstructured":"Mucha P Kus F Cysewski D et al. 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