Catgut down to the desired diameter using a centerless grinder. After drying and polishing, workers bleach and disinfect the strings using sulfur dioxide, dye them if necessary, and sort them into sizes. Catgut sutures are normally treated with a chromium salt solution to resist body enzymes, to slow the absorption process, and are called catgut chromic sutures—whereas untreated catgut sutures are called catgut plain sutures. Catgut Catgut 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,
Setar Setar The Setar (, from ', meaning "three" and ', meaning "string") is an Iranian musical instrument. It is a member of the lute family, which is played with the index finger of the right hand. Two and a half centuries ago, a fourth string was added to the Setar which most of the time has the same tone of the bass string. It has 25–27 moveable frets which are usually made of animal intestines or silk. Setar covers about 2 and a half scale (depending on the length the handle). some musicians even use its different strings like chords