An exudate is any fluid that filters from the circulatory system into lesions or areas of inflammation. It can apply to plants as well as animals. Its composition varies but generally includes water and the dissolved solutes of the main circulatory fluid such as sap or blood. In the case of blood: it will contain some or all plasma proteins, white blood cells, platelets and (in the case of local vascular damage) red blood cells. In plants it can be a healing and defensive response to repel insect attack or it can be an offensive habit (to repel other incompatible or competitive plants). Organisms that feed on exudate are known as exudativores for example, Vampire Bats who exhibit hematophagy.