The present invention relates to a feed supplement and a feed containing this feed supplement, comprising 1) a homotrimer, heterotrimer, homotetramer and/or heterotetramer of a carbohydrate component selected from the group consisting of a pentose saccharide, a hexose saccharide, glucuronic and galacturonic acid, and 2) a medium-chain fatty acid (MCFA), selected from the group consisting of caproic acid (C6), caprylic (C8), capric (C10) and lauric acid (C12). The invention also refers to the use of the feed supplement or feed in order to improve the efficiency of animal production, such as weight gain, feed conversion, nutritive value, health and wellbeing through the selective elimination of enteropathogens.