How to apply eye drops to a rat? - briefly
Restrain the rat gently, tilt the head backward, and dispense a single sterile drop onto the eye surface with a pipette, ensuring the tip does not contact the cornea. Keep the eyelids closed for several seconds to promote absorption, then observe for any signs of irritation.
How to apply eye drops to a rat? - in detail
Administering ocular drops to a laboratory rat requires careful preparation, precise technique, and post‑application observation to ensure effective delivery and animal welfare.
Preparation begins with assembling sterile supplies: a calibrated dropper or micropipette, the prescribed ophthalmic solution, sterile gauze, disposable gloves, and a clean work surface. Verify the concentration and volume required for the species, referencing the experimental protocol. Label the dropper with the drug name and expiration date to avoid cross‑contamination.
Restraint of the animal must minimize stress. Place the rat in a padded restraining device or gently hold it on a soft cloth with one hand supporting the thorax. Use the opposite hand to secure the head by lightly grasping the skin behind the ears, avoiding excessive pressure on the orbital region.
The administration steps are:
- Pull the lower eyelid downward with a sterile fingertip or a fine forceps to create a small pocket.
- Position the dropper tip just above the ocular surface, ensuring no contact with the eye or surrounding fur.
- Release a single drop (approximately 5 µL) into the pocket; the fluid will spread across the cornea by capillary action.
- Maintain the eyelid in the lowered position for 1–2 seconds to allow absorption, then release the eyelid.
- Observe the eye for signs of excess fluid; gently blot any overflow with sterile gauze.
After delivery, return the rat to its home cage and monitor for at least five minutes. Record any immediate reactions such as blinking, tearing, or rubbing, and note the time of administration in the experimental log. If multiple doses are required, repeat the procedure at the prescribed intervals, ensuring a minimum interval of 10 minutes between applications to prevent corneal irritation.
Clean and disinfect all equipment after each use. Dispose of used gloves and gauze in biohazard containers. Maintain a temperature‑controlled environment (20–24 °C) and provide access to food and water during the observation period.