What do you paint mice with? - briefly
Use a non‑toxic, water‑based acrylic paint applied with a fine brush; it adheres to fur and skin while remaining safe for the animal.
What do you paint mice with? - in detail
The choice of medium for applying color to laboratory mice depends on the intended purpose, duration of exposure, and animal welfare considerations.
Acrylic-based dyes, diluted with sterile water, provide quick drying and strong adhesion to fur. They are suitable for short‑term marking, such as identification during a single experiment. Commercially available rodent marking kits often contain these acrylic pigments, pre‑mixed to a non‑toxic concentration (typically 0.5‑2 % v/v).
Water‑soluble tempera paints are another option. When mixed with a mild surfactant (e.g., 0.1 % Tween‑20) they spread evenly and can be removed with a gentle saline rinse. Tempera is appropriate for multi‑day studies where frequent re‑application is unnecessary.
For long‑lasting marks, non‑volatile oil‑based paints formulated for animal use are employed. These contain a low‑toxicity carrier oil (such as mineral oil) and pigment concentrations below 1 %. Application requires a thin layer to avoid occluding the skin and must be followed by a curing period of 15‑20 minutes before the animal is returned to its cage.
When color identification is needed without direct skin contact, spray‑on pigments can be used. Aerosol formulations with a fine mist of diluted acrylic pigment allow rapid coverage of the dorsal coat. Safety measures include applying the spray in a ventilated area and wearing a mask to prevent inhalation.
Key considerations for any medium:
- Toxicity: Verify that the product is labeled as non‑toxic for rodents; avoid solvents such as ethanol, acetone, or xylene.
- Viscosity: Low‑viscosity solutions spread without clumping, reducing the risk of hair matting.
- Removal: Choose pigments that can be washed off with warm saline or mild soap without irritating the skin.
- Durability: Match pigment persistence to the experimental timeline; short‑term studies favor water‑based paints, long‑term studies may require oil‑based or spray formulations.
Proper application technique includes restraining the mouse gently, using a fine brush or cotton swab to apply a thin, even layer, and allowing the paint to dry completely before handling. Monitoring the animal for signs of stress or skin irritation after marking is essential for compliance with animal welfare protocols.