How can drops be administered into a rat's nose? - briefly
Place the rat in a supine position, gently insert a calibrated pipette tip into one nostril, and deliver the prescribed volume of liquid dropwise. Keep the animal upright for a brief period to permit even distribution throughout the nasal cavity.
How can drops be administered into a rat's nose? - in detail
Intranasal delivery of liquid formulations to a laboratory rat requires precise handling to ensure accurate dosing and minimal distress. The animal should be acclimated to the testing environment and fasted for a brief period (typically 2–4 hours) to reduce the risk of aspiration.
Essential supplies include a calibrated microsyringe (10–100 µL capacity) with a blunt‑ended needle or a micropipette, a stereotaxic frame or restraining device, sterile saline or vehicle for dilution, and a clean work surface. All instruments must be sterilized and the dosing solution prepared under aseptic conditions.
The procedure proceeds as follows:
- Position the rat in a supine orientation on a warmed platform; gently extend the head to expose the nares.
- Secure the animal using a soft restraint to prevent movement without causing excessive pressure on the neck.
- Load the desired volume (commonly 5–10 µL per nostril) into the syringe or pipette, avoiding air bubbles.
- Align the tip of the delivery device with the external naris, ensuring it contacts the vestibular opening without penetrating the nasal cavity.
- Slowly dispense the liquid, allowing the animal to inhale naturally; pause briefly between nostrils if dosing both sides.
- Observe the rat for signs of choking or regurgitation; if observed, gently clear the airway with a sterile swab.
After administration, keep the animal in a quiet recovery area for at least 15 minutes, monitoring respiration and behavior. Verify successful delivery by inspecting the nasal mucosa for residual fluid or using a dye marker in pilot studies. Record the exact volume, concentration, and time of dosing for reproducibility.