{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,2,4]],"date-time":"2025-02-04T05:12:29Z","timestamp":1738645949454,"version":"3.35.0"},"reference-count":29,"publisher":"American Veterinary Medical Association (AVMA)","issue":"2","license":[{"start":{"date-parts":[[2025,2,1]],"date-time":"2025-02-01T00:00:00Z","timestamp":1738368000000},"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":[[2025,2,1]]},"abstract":"<jats:title>Abstract<\/jats:title>\n<jats:sec id=\"sc_a1\">\n<jats:title>OBJECTIVE<\/jats:title>\n<jats:p>To describe the outcome of megaesophagus in harbor seal pups undergoing rehabilitation from January 2021 to December 2023.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sc_a2\">\n<jats:title>METHODS<\/jats:title>\n<jats:p>5 harbor seal (<jats:italic>Phoca vitulina richardii<\/jats:italic>) pups, 2 males and 3 females, were included in the study. All 5 cases had no clinical signs associated with megaesophagus on initial presentation to the rehabilitation facility. Case 1 presented with regurgitation, diarrhea, bloating, and poor gain of body mass starting 24 days into rehabilitation. Case 2 presented with regurgitation and bloating on day 12. Case 3 presented with hyporexia, bloating, poor gain of body mass, and regurgitation between days 55 and 60. Case 4 presented with lethargy, diarrhea, and regurgitation starting on day 12 of rehabilitation. Case 5 presented with difficulty gavage feeding 14 days into rehabilitation and regurgitation starting day 28. Radiographs in all 3 cases revealed dilation of the esophagus and gas distention of the stomach and intestines, consistent with megaesophagus. Cases 1, 2, and 3 were treated with 1 mg\/kg sildenafil by mouth every 12 hours for 14 days at the time of diagnosis.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sc_a3\">\n<jats:title>RESULTS<\/jats:title>\n<jats:p>Cases 1 and 2 showed improvement in radiographic lesions and resolution of clinical signs after treatment and were released after 1 and 3 months of posttreatment monitoring respectively. None of the clinical signs returned after medications were discontinued. Postrelease survival was monitored in case 2 via a satellite-linked transmitter for 39 days. Case 3 was euthanized due to worsening lethargy, difficulty tube feeding, and continued loss of body mass after 6 days of treatment. Case 4 was euthanized at the time of diagnosis of megaesophagus on radiographs due to dull mentation and declining clinical status, and case 5 died a few hours after diagnosis of megaesophagus on radiographs before sildenafil treatment could be initiated.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sc_a4\">\n<jats:title>CONCLUSIONS<\/jats:title>\n<jats:p>Sildenafil successfully managed megaesophagus in 2 of 3 <jats:italic>P vitulina richardii<\/jats:italic> juveniles. This case series highlights that sildenafil may be a potential treatment option for megaesophagus in <jats:italic>P vitulina richardii<\/jats:italic> pups undergoing rehabilitation.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sc_a5\">\n<jats:title>CLINICAL RELEVANCE<\/jats:title>\n<jats:p>Based on the results of these cases, it is hypothesized that megaesophagus in rehabilitated harbor seals is not always a congenital defect but possibly an iatrogenic condition.<\/jats:p>\n<\/jats:sec>","DOI":"10.2460\/ajvr.24.09.0281","type":"journal-article","created":{"date-parts":[[2024,12,5]],"date-time":"2024-12-05T15:26:01Z","timestamp":1733412361000},"source":"Crossref","is-referenced-by-count":0,"title":["Successful treatment of megaesophagus with sildenafil in juvenile Pacific harbor seals (Phoca vitulina richardii) undergoing rehabilitation"],"prefix":"10.2460","volume":"86","author":[{"given":"Treasa C.","family":"Deegan","sequence":"first","affiliation":[{"name":"Vancouver Aquarium, Vancouver, BC, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lindsaye","family":"Akhurst","sequence":"additional","affiliation":[{"name":"Vancouver Aquarium, Vancouver, BC, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0097-5575","authenticated-orcid":true,"given":"Sarah E.","family":"Wright","sequence":"additional","affiliation":[{"name":"Publications Division, American Veterinary Medical Association, Schaumburg, IL"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Martin","family":"Haulena","sequence":"additional","affiliation":[{"name":"Vancouver Aquarium, Vancouver, BC, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1272","reference":[{"issue":"6","key":"B1","series-title":"J Vet Intern Med","first-page":"1314","article-title":"Esophageal dysmotility in young dogs","volume":"20","author":"Bexfield NH","year":"2006","unstructured":"Bexfield NH, Watson PJ, Herrtage ME. 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