Exploring age‐ and sex‐specific survival rates provides insight regarding population behavior and life‐history trait evolution. However, our understanding of how age‐specific patterns of survival, including actuarial senescence, compare between the sexes remains inadequate. Using 36 years of mark‐recapture data for 7,516 male Weddell seals (
Weddell seals (
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.
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.
The sample size is small and there is no pharmacokinetic information for either sedative or reversal in phocid species.
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.
- NSF-PAR ID:
- 10376033
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Veterinary Record
- Volume:
- 191
- Issue:
- 11
- ISSN:
- 0042-4900
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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