Diabetes is one of the most common diseases in cats. Treatment often involves giving insulin and regularly monitoring sugar levels. Typically, a cat’s sugar levels are checked through a test called a blood glucose curve (BGC). BGCs help us understand how well the diabetes treatment is working. With the proper tools, BGCs can be performed either by a veterinarian or by the owner themselves. This process requires pricks of the cat’s skin to obtain a small drop of blood and measuring with a device known as a glucometer every 2 hours for 8-12 hours. To help with this process, a device called a continuous glucose monitor (CGM) was developed for humans and can be used in cats. A CGM contains a small sensor that can continuously measure a cat’s sugar levels for up to 14 days without repeated pricks. Many families find this method of monitoring sugar levels easier and less stressful for them and their cat.

The FreeStyle Libre is the most used CGM in cats. The newest model, the FreeStyle Libre 3 (FSL3), differs from the original by automatically sending sugar levels from the sensor to a registered smartphone or standalone reader. The first model must be scanned with a smartphone to regularly record measurements, which is not helpful for people who cannot scan the device every 8 hours or do not have a compatible phone. The ability for the newest model to continuously measure sugar levels can increase the amount of sugar readings taken. This can then help veterinarians make better treatment recommendations and help researchers study diabetes. The FSL3 is also smaller than the original model, possibly being more comfortable for cats. However, we do not know how accurate the FSL3 is in diabetic cats. Our study, therefore, aims to test the accuracy of the device in diabetic cats. We think the FSL3 will provide accurate sugar measurements and will help veterinarians decide treatment options, ultimately resulting in a better life for diabetic cats and their families.