How to Make a Rat Infusion Cage

Setting up a cage for tethered infusion can be difficult. If not done right, you may face a range of problems such as twisted tethers, tethers destroyed by biting, seromas caused by repeated impact of the VAB™ on the cage, or restricted movement, all of which can ruin your experiment and impact animal welfare.

In this post we'll start with a good conventional rat cage from Tecniplast and turn it into an infusion cage with these critical features:

• Slotted lid to allow the tether to travel the length of the cage
• Counter-balanced swivel mount to remove slack from the tether
• Tether of the correct length for the size of the cage
• Proper clearance for the Vascular Access Button™ on the back of the animal

Start With the Right Cage

For our cage we've chosen the Tecniplast 1291H Eurostandard Type III H rat cage and a series -123 raised wire lid. The 1291H is 185mm tall, which you need to have clearance for the VAB™. The raised wire lid works perfectly with standard 12in/30cm tethers, plus rats can stand on hind legs which is good for their welfare.

Slot the Cage Lid

Next we'll show you how to slot the lid so that the tether can move freely.

Materials Required: Safety glasses, Cutting/Grinding disc, Dremel Tool, Clamp, Marker, Needlenose pliers, Safety gloves, Ruler, Cage Top (Tecniplast series -123).

Instructions

Step 1: Mark Cage Top for Cutting — Firmly secure the cage top to a stable surface, find the center point, and mark the segments of cage to be cut.

Step 2: Spread Wire for Tether Insert — Insert your pliers centered between the two cross sectional bars on top of your cage, then rotate your pliers 90 degrees so the width of the pliers spreads and bends the wire caging.

Step 3: Cut Wire — While wearing safety glasses and gloves, use your Dremel tool to cut the wires at all four locations. Grind any sharp edges.

Attach the Swivel Mount

The Instech CM375KRP mount is ideal for this kind of cage when working with rats and plastic swivels. The simple spring arm removes slack from the tether and minimizes forces on the animal and the surgical site.

Connect an Infusion Tether

The height of this cage with the CM375KRP mount is a good fit with standard 12in/30cm spring tethers. You'll know you have a good fit when the arm is fully upright when the animal is in the center of the cage and there is no slack in the tether.