Mesenteric arteries

The mesenteric arteries are the arteries that provide blood to most of the digestive tract. It branches off directly from the aorta.The mesenteric arteries are not the only set of arteries that supply blood to the digestive tract, so a blockage in one of the arteries generally will not cut off all blood flow to the area. 
The smaller mesenteric artery branches have a high variability of resistance to blood flow, allowing more or less blood to flow to a particular area when digestion requires it. They can also contract to restrict blood flow when blood is urgently required elsewhere, such as during exercise or when a patient is suffering from shock.
Mesenteric arteries at Wikipedia