In which of these is a type of cord called "catgut" used?

Catgut (also known as gut) is a type of cord that is prepared from the natural fibre found in the walls of animal intestines. Catgut makers usually use sheep or goat intestines, but occasionally use the intestines of cattle, hogs, horses, mules, or donkeys. Despite the name, catgut manufacturers do not use cat intestines.

Catgut suture was once a widely used material in surgical settings. There is debate about whether to continue using catgut in a medical setting, since cotton is usually cheaper and wounds closed with either cotton or synthetic threads are less prone to infection. Catgut sutures remain in use in developing countries where they are locally less expensive and easier to obtain. Catgut treated with chromium salts, known as chromic catgut, is also used in surgery.