How can medicine be fed to a rat? - briefly
Researchers typically deliver drugs to rodents by oral gavage, mixing the compound into a palatable suspension or using a feeding needle for direct dosing. Alternative routes include subcutaneous, intraperitoneal, or intravenous injection, chosen according to pharmacokinetic needs.
How can medicine be fed to a rat? - in detail
Administering therapeutic agents to laboratory rats requires precise dosing, appropriate delivery method, and strict adherence to animal‑care protocols.
First, determine the required dose in milligrams per kilogram of body weight. Weigh the animal, calculate the dose, and convert it to the volume of the formulation using the concentration of the drug. Record all calculations for reproducibility.
Oral delivery
- Gavage: Use a calibrated stainless‑steel or flexible gavage needle (20–22 G). Insert the needle gently into the esophagus, avoiding the trachea. Deliver the measured volume slowly, then withdraw the needle and observe the rat for regurgitation.
- Food or water incorporation: Dissolve or suspend the compound in a palatable carrier (e.g., flavored gel, peanut butter) or in drinking water. Verify stability of the drug in the medium and monitor individual consumption to ensure dose accuracy.
Parenteral routes
- Intraperitoneal (IP) injection: Choose a 25–27 G needle, inject into the lower right quadrant of the abdomen at a 30–45° angle. Aspirate before injection to confirm no blood return.
- Subcutaneous (SC) injection: Pinch a loose area of dorsal skin, insert the needle bevel up at a shallow angle, and inject the solution.
- Intravenous (IV) injection: Access the lateral tail vein with a 30–32 G needle or catheter. Apply gentle restraint, warm the tail to dilate vessels, and inject the drug slowly to prevent vein collapse.
Special considerations
- Use sterile, pyrogen‑free syringes and needles for each animal.
- Maintain the drug at the recommended temperature; some compounds require refrigeration or warming before administration.
- Observe the rat for immediate adverse reactions (e.g., respiratory distress, lethargy) and record findings.
- Provide post‑administration monitoring for at least 30 minutes, then continue regular health checks.
Documentation
- Log animal ID, weight, calculated dose, administration route, volume, and any observations.
- Store records in compliance with institutional animal‑care guidelines and regulatory requirements.
Following these procedures ensures accurate, humane, and reproducible delivery of medication to rats in experimental settings.