Promethion Mouse Cage Assembly

The Promethion mouse cage is an integral component of the Promethion high-throughput metabolic behavioral phenotyping system. It serves as a long-term habitat and respirometry chamber. Mass monitoring units measure real-time food and water uptake and changes in body mass. An infrared beam break array and a running wheel monitor activity and behavior. Access control doors allow researchers to limit food access and also can be used for food choice experiments. The cage controller communicates all of these data streams on a second-by-second basis for each individual cage.

Each phenotyping cage consists of more than 15 separate components. Proper assembly of the mouse cage is a key step in high-throughput metabolic phenotyping. First, attach the running wheel to the lid. Lift the wheel so that the reed switch holder faces forward. Slide the screws through the mounting holes. Then fit the washers over the screws. Then secure the wheel in place using the wing nuts.

Attach the AC2, the access control doors, to the lid. Slide the screws through the mounting holes. And secure the AC2 in place using the thumb nuts. Insert the air sampling manifold. Take note, this manifold has precision laser-cut holes along the bottom length for evenly distributed air sampling throughout the cage. Place the manifold inside the cage and lower the lid over the uprights.

Now the mass monitors, the MM2, and the food, water, and body mass hoppers can be added to the cage. First, fill the food hopper with rodent chow. Make sure not to overfill the hopper because too much food could interfere with the MM2 function. Slide the MM2’s mounting bracket over the registration pins and swivel the safety catch in place. Place the MM2 in the slot across from the AC2. Note the registration pins and let the magnets snap onto the lid.

Next, fill the water bottle with 125 milliliters of water. Carefully seal the rubber stopper. Make sure the sipper tube is perpendicular to the bottle’s front edge. Place the bottle in the water hopper. Check to ensure that the sipper tube is facing forward toward the center of the cage. Attach the MM2. Place the water hopper into the slot next to the food hopper.

Third, attach the animal habitat hopper to its MM2 and place it in the final slot. Connect the air sampling tube and filter assembly to the manifold. Make sure the elbow push-to connectors are seated properly. The cage is now complete.

Next, assemble the beam break arrays. Place the base on the table and slide the XY array into the mounts. Slide the XY array’s attachment screws into slot number 2. This will keep it just off the ground. Now slide the Z array into the mounts. Set the Z array’s attachment screws into slot number 5 using the thumb nuts. Attach the cage controller, the CC2, in line on the rear mount. The beam break array is now complete.

Place the cage inside the beam break array. To ensure consistent beam break coverage, slide the cage to the left rear corner. Then insert the reed switch rotation sensor. Plug the reed switch into the CC2 into the special socket labeled “wheel”. Note the difference between the reed switch plug size and the TRRS plugs. Plug a TRRS cable into the beam breaks one end into the XY array and the other to the Z array. The common end goes into the CC2 in the data 1 slot. Plug a Trident cable into the three MM2s. The common end of that cable goes into the CC2 in the data 2 slot. Plug the single TRRS cable into the AC2 and the other end into the CC2 in the data 3 slot. The mouse cage assembly is now complete. The cage is ready to be placed in a Promethion CGF system.

For data acquisition and control, plug an RJ45 cable into the CC2 data port and transfer the cage into the Promethion CGF system. Once the cage is in place, plug the other end of the RJ45 cable into the cabinet’s slot number 1. Connect an air sampling tube to the filter. Make sure the push to connect seats properly. Connect the tube to the cabinet’s air sample slot 1. The cage is now fully connected to the CGF.

Add approximately 500 milliliters of one-half centimeter or 1 quarter inch cob bedding material into the cage tub. Carefully level the bedding material before replacing the cage lid. Make sure the running wheel clears the top layer of the bedding material. Now the cage is ready to receive a mouse for data acquisition. A properly assembled cage can accommodate a mouse for at least one week.