Feedback, is a common practice used in the pork industry where infected deceased pigs and their manure are fed to breeding pigs. It it also called controlled oral exposure or sometimes oral controlled exposure. It is done in an attempt to make the breeding pigs garner some degree of immunity to circulating diseases.[1] There is no standard protocol resulting in some swine researchers calling the procedure potentially risky and noting that it is often done in an unsafe manner.[2][3] The practice has also been criticized by animal welfare and animal rights groups calling it disturbing and or unethical.