Consumers are increasingly concerned about the impact of nutrition on their health. They want pork products devoid of antibiotic residues because of fears that the latter could be responsible for the development of bacteria resistant to antibiotics. Pork producers are aware that the pig gastrointestinal tract must remain healthy in order to maximize the use of the nutrients and to prevent the occurrence of diarrhoea. Different alternatives are currently tested in many laboratories. Among them, “prebiotics” are of particular interest. These plant extracts are used as substrates by health-promoting bacteria (Lactobacilli, Bifidobacteria) and the latter grow at the expense of pathogenic ones (Salmonella, E. coli) in the pig tract. Different indigestible carbohydrates are used as substrates by health-promoting bacteria such as Lactobacilli in the pig gastrointestinal tract. Some specialty hulless barleys contain high amounts of these indigestible carbohydrates. This experiment aimed at evaluating the possibility to use hulless barleys as a health-promoting factor in swine nutrition. Hulless barleys were better digested than hulled barleys and oats. Their presence in the gut also generated the production of higher amounts of short-chain fatty acids and led to the disappearance of some pathogenic bacteria strains in the upper part of the gastrointestinal tract. This confirms the potential of specialty hulless barleys as health-promoters in swine nutrition.