Motion acid is a slow and controlled release acidifier. It is a combination of selected organic and inorganic acids coated and protected by a matrix of fatty acids. Unlike products made of free acids,it does not affect the cells of stamach wall and acidifiers without lowering the normal production of hydrochloric acid.It works slowly and progressively in the stomach and predominantly in the intestine under the action of lipase and biliary salts. The specific fatty acid coating of it allows a slow and controlled release of the acids: 1.30% of the acids are liberated in the stomach to help he hydrolysis of proteins and maintain a physiologically effective pH without reducing the endogenous production of HCI. 2.70% of the acids are slowly released in the intestine after the hydrolysis of the fatty acid coating,under the action of pancreatic lipase and biliary salts. The efficacy of it as an acidifier to the intestinal contents of pigs,deep in the digestive tract. It explains why the composition and the shedding of the intestinal microflora of pigs is greatly modified when it is administered. It opens interesting perspectives for the use of it in sows to lower the shedding of bacteria and minimize the exposure of newborn piglets to pathogens. It is for pig feed.