Source: Kay Stewart, RVT, RLATG, CMAR; Valerie A. Schroeder, RVT, RLATG. University of Notre Dame, IN

There are many commonly used routes for compound administration in laboratory mice and rats. Protocols may, however, require the use of the less commonly used routes: intracardiac, footpad, and retro-orbital injections. Specialized training is essential for these procedures to be performed successfully. Justification for these routes may need to be provided to gain Institutional Animal Care and Use Committee (IACUC) approval.

1. Intracardiac injection

1. Landmarks and positioning: Position the mouse or rat either in right lateral recumbency (with the left side facing upward) or in dorsal recumbency, and identify the landmarks.
   1. Position the heart approximately level with the point of the elbow and just to the left of the sternum.
   2. Insert the needle between the ribs at the point of the elbow.
   3. In an animal in dorsal recumbency, insert the needle into the chest parallel to the table.
   4. In an anim

The administration of compounds into animals can have a significant effect on both the wellbeing of the animal and the outcome of the experimental data and scientific value. The proper method of delivery is essential to the success of the experiment. Many factors must be considered to determine the best route, including the scientific aim of the study, the pH of the substance, the required dosage volume, the viscosity of the substance, and the wellbeing of the animals. Technical expertise is also a requirement for all in

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