The material used for sutures (stitches) is called surgical suture, and it's made from a variety of materials like:
* Synthetic materials: These are the most common, and include nylon, polyester, polypropylene, and others.
* Natural materials: These include silk, cotton, and catgut.
Catgut, which is made from the intestines of sheep or other animals, is a natural material that was used for sutures historically. However, it is not made from cats, and its use has largely been replaced by synthetic materials.
So, there's no need to worry about cats being harmed for the purpose of making stitches.