{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,14]],"date-time":"2025-10-14T07:17:57Z","timestamp":1760426277430,"version":"build-2065373602"},"reference-count":21,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2025,3,5]],"date-time":"2025-03-05T00:00:00Z","timestamp":1741132800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Animals"],"abstract":"<jats:p>California sea lions (Zalophus californianus) are susceptible to various ocular diseases, with some literature suggesting a heightened risk for those kept in freshwater pools as opposed to saltwater. Given the potential implications of housing conditions on animal health, we wanted to analyze the ocular health of two distinct groups of California sea lions kept at Nuremberg Zoo, one housed in freshwater and the other in saltwater. Data extracted from the animals\u2019 medical records during a ten-year period were used to compare the incidence of eye conditions and other medical conditions observed. The results revealed no significant difference in the overall occurrence of eye diseases between the two environments. However, a distinct seasonal pattern was noted: California sea lions kept in freshwater exhibited a peak in eye disorders during the summer months, while those in saltwater displayed a more uniform distribution of the occurrence of ocular diseases throughout the year. These findings suggest that sun exposure and water quality are potentially more influential factors in the development of ocular diseases in pinnipeds than salinity. Further studies are necessary to elucidate the underlying mechanisms and optimize care practices for these marine mammals.<\/jats:p>","DOI":"10.3390\/ani15050739","type":"journal-article","created":{"date-parts":[[2025,3,5]],"date-time":"2025-03-05T03:18:22Z","timestamp":1741144702000},"page":"739","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Occurrence of Ocular Disorders in California Sea Lions Under Human Care: Comparing Freshwater and Saltwater Housing Conditions"],"prefix":"10.3390","volume":"15","author":[{"given":"Ingrid","family":"Brehm","sequence":"first","affiliation":[{"name":"Animal Physiology, Friedrich-Alexander Universit\u00e4t Erlangen-N\u00fcrnberg, 91058 Erlangen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Silas","family":"Herzner","sequence":"additional","affiliation":[{"name":"Animal Physiology, Friedrich-Alexander Universit\u00e4t Erlangen-N\u00fcrnberg, 91058 Erlangen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Katrin","family":"Baumgartner","sequence":"additional","affiliation":[{"name":"Nuremberg Zoo, 90480 Nuremberg, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"J\u00f6rg","family":"Beckmann","sequence":"additional","affiliation":[{"name":"Nuremberg Zoo, 90480 Nuremberg, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ralph","family":"Simon","sequence":"additional","affiliation":[{"name":"Nuremberg Zoo, 90480 Nuremberg, Germany"},{"name":"Behavioral Ecology and Conservation Lab, Nuremberg Zoo, 90480 Nuremberg, Germany"},{"name":"Machine Learning and Data Analytics Lab, Friedrich-Alexander Universit\u00e4t Erlangen-N\u00fcrnberg, 91058 Erlangen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3451-0530","authenticated-orcid":false,"given":"Lorenzo","family":"von Fersen","sequence":"additional","affiliation":[{"name":"Nuremberg Zoo, 90480 Nuremberg, Germany"},{"name":"Behavioral Ecology and Conservation Lab, Nuremberg Zoo, 90480 Nuremberg, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,3,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Montiani-Ferreira, F., Moore, B.A., and Ben-Shlomo, G. (2022). Ophthalmology of Pinnipedimorpha: Seals, Sea Lions, and Walruses. Wild and Exotic Animal Ophthalmology, Springer.","DOI":"10.1007\/978-3-030-81273-7"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"429","DOI":"10.2460\/javma.237.4.429","article-title":"Risk factors associated with cataracts and lens luxations in captive pinnipeds in the United States and the Bahamas","volume":"237","author":"Colitz","year":"2010","journal-title":"J. Am. Vet. Med. Assoc."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"224","DOI":"10.2460\/javma.255.2.224","article-title":"Factors associated with keratopathy in captive pinnipeds","volume":"255","author":"Colitz","year":"2019","journal-title":"J. Am. Vet. Med. Assoc."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"47","DOI":"10.1111\/j.1463-5224.2010.00811.x","article-title":"Characterization of progressive keratitis in otariids","volume":"13","author":"Colitz","year":"2010","journal-title":"Vet. 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Available online: https:\/\/studenttheses.uu.nl\/handle\/20.500.12932\/9560."}],"container-title":["Animals"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2076-2615\/15\/5\/739\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,9]],"date-time":"2025-10-09T16:47:19Z","timestamp":1760028439000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2076-2615\/15\/5\/739"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,3,5]]},"references-count":21,"journal-issue":{"issue":"5","published-online":{"date-parts":[[2025,3]]}},"alternative-id":["ani15050739"],"URL":"https:\/\/doi.org\/10.3390\/ani15050739","relation":{},"ISSN":["2076-2615"],"issn-type":[{"type":"electronic","value":"2076-2615"}],"subject":[],"published":{"date-parts":[[2025,3,5]]}}}