Fistulation surgery is relatively straightforward with no effect on the health or longevity of the cow and are performed frequently at universities. Surgeries are performed standing and under local anesthesia. A permanent hole between the rumen (compartment of stomach) and the outside world is established by surgically attaching the rumen to the skin and the body wall. A cannula (tube made of plastic) is placed between the rumen and skin to create a seal. A removable cap is included for easy access into the rumen to retrieve microorganisms.
Microorganisms are very important for proper digestive function in ruminants. Transfaunation is the act of taking microbes from one source and putting into another source. Transfaunation is used in bovine surgery patients to increase recovery rate, return appetite, and increase milk production with reestablished gut flora. Fistulation is also helping improve research in bovine nutrition by being able to sample contents from the rumen.