Midazolam sedates Passeriformes for field sampling but affects multiple venous blood analytes

Area of Science:

• Veterinary Medicine
• Avian Biology
• Wildlife Research

Background:

• Sedation is crucial for handling wild birds during research.
• Assessing the physiological effects of sedatives on avian blood analytes is important for study integrity.
• Midazolam is a potential sedative agent for avian species.

Purpose of the Study:

• To evaluate the feasibility and effects of intranasal midazolam for sedating passerine birds.
• To determine the impact of midazolam on blood analytes in passerine birds.
• To assess the safety and efficacy of midazolam for short-term use in free-living passerines.

Main Methods:

• 104 passerine birds received intranasal midazolam (5.6±2.7 mg/kg) before sampling and euthanasia.
• Sedation scores were assessed, and blood samples were analyzed using an i-STAT point-of-care analyzer.
• Key blood analytes, including electrolytes and blood gases, were measured.

Main Results:

• Most birds achieved acceptable sedation, with increased sedation correlating with higher midazolam doses.
• Midazolam administration affected electrolyte concentrations and venous blood gas analytes.
• Blood pH, packed cell volume, hemoglobin, and calculated hematocrit remained unaffected.
• Only one bird mortality was recorded.

Conclusions:

• Intranasal midazolam provides adequate and safe short-term sedation for free-living passerine birds.
• Sedation may reduce stress but can cause hypoventilation-like blood gas changes.
• Further research is recommended on midazolam's safety, recovery, and compatibility with ecological and toxicological studies.