Apr 08, 2026
GI function test
- 1KU Leuven
Protocol Citation: Ana Cascalho, Hanne Dhondt 2026. GI function test. protocols.io https://dx.doi.org/10.17504/protocols.io.bp2l62k9rgqe/v1
License: This is an open access protocol distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
Protocol status: Working
We use this protocol and it's working
Created: March 14, 2024
Last Modified: April 09, 2026
Protocol Integer ID: 96900
Keywords: gi function test the gi function assay, gi function assay, gi function test, gi function, parameters like constipation, constipation, stool, blood in stool, diarrhea
Abstract
The GI function assay is used to assess GI function, including parameters like constipation, diarrhea and blood in stool.
Attachments
Guidelines
- Stool collection assays are ideally performed between 9:00 am and 11:00 am on each day.
- Most feeding/defecation behavior occurs at night, so it is beneficial to run the experiment in a low light setting.
- Handling, room temperature and hour of the day impact results and should be maintained uniform along experimental days and experimental groups.
- Female mice pellet production is reduced if housed next to a male, therefore for the analysis females and males should be kept spatially isolated (different cages) to avoid odor influences.
Materials
Materials:
- Tripods
- Cameras with chargers
- Clean/spare cages
- Timer
- Pens
- Extra cards for animal/cage ID
- LabBook
- Labelled Eppendorf tubes and tube rack
- Tweezer
- Cage lids for separation
GI function assay
19h
Bring the mice to the analysis room 00:30:00 before analysis.
30m
Remove each animal from its home cage and place in a clean plastic cage, with a lid, without food or water for 01:00:00 .
1h
After the testing time, transfer the mice back to their home cage.
Take a picture of cage bottom for recording of pellet number.
Collect stools immediately and place in sealed tubes.
At the end of the trial, count and weigh the stools (total weight), then dry o/n (18:00:00 ) at 65 °C and weigh again to provide dry weight. Take a picture of the tubes (with the dry stools visible).
18h
Calculate the water content as a difference between total weight and dry weight.
Note
- Stool moisture content = [(A-B)/A] × 100 , where A is the weight of fresh stools collected after drug administration minus the average weight of an empty eppendorf tube (0.94 g), and B is the weight of stools after drying at 65 °C for 18:00:00 minus the average weight of an empty eppendorf tube (0.94 g).
- Incidence rate = Number of constipated mice/Total number of analyzed mice × 100.
Repeat the experiment for 2 times/week and take average values for statistical analysis per mouse.