A Safe and Effective Reversible Field Sedation Protocol for Weddell Seal Pups
- Medicine
Abstract
Background: Weddell seals (Leptonychotes weddellii) are a well-studied species of phocid with an apparent sensitivity to immobilising agents. Mortality as high as 31% has been reported during field immobilisation. This study investigated the use of a benzodiazepine in combination with an opioid agonist/antagonist for sedation in Weddell seal pups as part of a physiological study.
Methods: During the 2017 and 2019 Antarctic pupping seasons, 18 Weddell seal pups were sedated by intramuscular administration of a combination of midazolam and butorphanol or intravenous midazolam alone. Individuals were sedated at 1, 3, 5 and 7 weeks of age. Naltrexone and flumazenil were used to reverse sedation. The combination was 100% effective in providing appropriate sedation for the intended procedures.
Results: Analyses were performed to investigate relationships between dose administered, age, individual reactions, adverse effects and changes in dive physiology. Transient apnoea (10–60 seconds) was the most frequently observed adverse effect. No sedation-associated morbidity or mortality occurred.
Limitations: The sample size is small and there is no pharmacokinetic information for either sedative or reversal in phocid species.
Conclusions: The combination of midazolam (0.2–0.3 mg/kg) and butorphanol (0.1–0.2 mg/kg) provided safe and effective sedation, with reversible effects, in Weddell seal pups.
Whoriskey, S., Pearson, L.E., Harris, H.S., Whitmer, E.R., Liwanag, H.E., Brodie, E. and Johnson, S., 2022. Using a combination of midazolam and butorphanol is a safe and effective reversible field sedation protocol for Weddell seal (Leptonychotes weddellii) pups. Veterinary Record, p.e2238.
Heather S. Harris
Sophie Whoriskey
Meet The Experts
{"image":"\/People\/Portrait\/cropped-images\/sophie-whoriskey-by-bill-hunnewell-c-the-marine-mammal-center-0-0-2008-1489-1601938777.jpg","alt":"Sophie Whoriskey","title":"Sophie Whoriskey","text":"Associate Director, Hawai\u2019i Conservation Medicine","link_url":"https:\/\/www.marinemammalcenter.org\/person\/sophie-whoriskey","link_text":"Read Bio"}
{"image":"\/People\/Portrait\/cropped-images\/heather-harris-zoomed-out-1074-522-1419-1108-1701471795.jpg","alt":"Heather Harris","title":"Heather S. Harris","text":"Associate Veterinarian","link_url":"https:\/\/www.marinemammalcenter.org\/person\/heather-harris","link_text":"Read Bio"}
Related Publications
{"image":"\/Animals\/Patients\/Elephant seals\/cropped-images\/es-by-bill-hunnewell-c-the-marine-mammal-center-3-2-1214-3454-3512-1600891002.jpg","alt":"northern elephant seal","title":"Diagnostic Tests for Lungworm-Infected Northern Elephant Seals","link_url":"https:\/\/www.marinemammalcenter.org\/publications\/diagnostic-tests-for-lungworm-infected-northern-elephant-seals","label":"Research Paper"}
{"image":"\/Animals\/Patients\/California sea lions\/cropped-images\/csl-by-bill-hunnewell-c-the-marine-mammal-center-7-0-1446-2827-2208-1603918668.jpg","alt":"California sea lion on pool ledge","title":"Effectiveness of Antibiotics in Treating Leptospirosis in California Sea Lions","link_url":"https:\/\/www.marinemammalcenter.org\/publications\/effectiveness-of-antibiotics-in-treating-leptospirosis-in-california-sea-lions","label":"Research Paper"}
Effectiveness of Antibiotics in Treating Leptospirosis in California Sea Lions
Read More{"image":"\/Animals\/Wild\/Elephant seal\/cropped-images\/elephant-seal-bull-shutterstock-640-0-3728-2911-1626818513.jpg","alt":"large northern elephant seal on a beach","title":"Use of Potassium Chloride for Low-Residue Euthanasia of Anesthetized Seals and Sea Lions","link_url":"https:\/\/www.marinemammalcenter.org\/publications\/use-of-potassium-chloride-for-low-residue-euthanasia-of-anesthetized-seals-and-sea-lions","label":"Research Paper"}
Use of Potassium Chloride for Low-Residue Euthanasia of Anesthetized Seals and Sea Lions
Read More{"image":"\/Animals\/Patients\/Guadalupe fur seals\/gfs-tagging-by-bill-hunnewell-c-the-marine-mammal-center-noaa-permit-18786.jpg","alt":"researchers apply a satellite tag to a Guadalupe fur seal","title":"Inhalant Anesthesia for Minimally Invasive Procedures in Guadalupe Fur Seals","link_url":"https:\/\/www.marinemammalcenter.org\/publications\/inhalant-anesthesia-for-minimally-invasive-procedures-in-guadalupe-fur-seals","label":"Research Paper"}
Inhalant Anesthesia for Minimally Invasive Procedures in Guadalupe Fur Seals
Read MoreRelated News
{"image":"\/Animals\/Patients\/Elephant seals\/cropped-images\/es-hoffman47927-photo-by-bill-hunnewell-c-the-marine-mammal-center-124-0-1270-992-1748384535.jpg","alt":"An An elephant seal\u2019s face with long black whiskers and wide eyes emerges from the water. ","title":"Adaptations of the Deep: Seal Whiskers and Eyes","link_url":"https:\/\/www.marinemammalcenter.org\/news\/adaptations-of-the-deep-seal-whiskers-and-eyes","label":"Patient Update","date":"2025-05-28 02:00:00"}
{"image":"\/Animals\/Wild\/Elephant seal\/cropped-images\/01. SNI Andromeda_NOAA permit-174-0-1270-992-1733414759.jpg","alt":"A northern elephant seal with a satellite tag on its head on the beach in front of crashing waves. ","title":"Studying Elephant Seals of the Central California Coast","link_url":"https:\/\/www.marinemammalcenter.org\/news\/studying-elephant-seals-of-the-central-california-coast","label":"News Update","date":"2024-12-06 12:21:47"}
{"image":"\/Animals\/Patients\/California sea lions\/2022\/cropped-images\/csl-torple-by-bill-hunnewell-c-the-marine-mammal-center-6-10-4475-3495-1664989112.jpg","alt":"California sea lion Torple in a pool with her head in the air","title":"SFGATE: Hundreds of Sea Lions Sickened Along California Coastline","link_url":"https:\/\/www.marinemammalcenter.org\/news\/sfgate-hundreds-of-sea-lions-sickened-along-california-coastline","label":"In the News","date":"2022-10-05 02:00:00"}
SFGATE: Hundreds of Sea Lions Sickened Along California Coastline
October 5, 2022
Read More{"image":"\/Animals\/Patients\/California sea lions\/2014\/cropped-images\/csl-orchard-photo-c-the-marine-mammal-center-1350-74-2950-2304-1713994848.jpg","alt":"California sea lion Orchard","title":"The Curious Case of the Sea Lion That Couldn\u2019t Catch His Breath","link_url":"https:\/\/www.marinemammalcenter.org\/news\/the-curious-case-of-the-sea-lion-that-couldnt-catch-his-breath","label":"Patient Update","date":"2014-11-19 01:00:00"}
The Curious Case of the Sea Lion That Couldn’t Catch His Breath
November 19, 2014
Read More