Galacto-oligosaccharides are prebiotics that occur naturally in breast milk and are known to play a role in building the healthy of infants at a time when their immune systems are undeveloped. They have also been used in foods aimed at adults, to help foster growth of beneficial bacteria in the gut and alleviate the symptoms of irritable bowel syndrome - as well as stomach upsets and diarrhoea. Now, however, researchers are looking at using prebiotics further up the food chain, in place of antibiotics to block pathogens and stop animals getting sick. Laura Searle from the Veterinary Laboratories Agency in the UK is today reporting positive findings on the use of a mixture of galacto-oligosaccharide mixture intended for human use, in a murine model. So far her work has centered around reducing the invasion capabilities of Salmonella typhimurium and reducing the seriousness of the symptoms in the mice. After treatment with the mixture, fewer Salmonella bacteria were found in systemic and intestinal tissues, she reports. Full details of the study and findings, which are being presented at the meeting of the Society for General Microbiology in Edinburgh, have not been seen by NutraIngredients.com prior to publication. However Searle said she is submitting her work to a scientific journal. Searle is now working to uncover the exact mechanism by which the galacto-oligosaccharises works, potentially also contributing to knowledge as to how they could help humans, too. Searle told NutraIngredients.com that research into the benefits of various prebiotics for humans indicates one mechanism by which they could work to be by stimulating normal flora in the gut so that they "out compete" with the pathogens. Although it is still early days, she said she hopes her work towards establishing a mechanism in animals could, ultimately, feed in to research on benefits for humans. Searle said that Salmonella typhimurium is of particular concern, "since we can trace people being infected through direct contact with animals or through the food chain". The use of prebiotics for farm animals is an interesting new area, driven by the EU ban on the use of antibotics as growth promoters and therapeutic agents for animals in 2006, since such use can lead to antibiotic resistance. This has meant there has been an urgent search for antibiotic alternatives to help animals resist infection. In addition to the bacteria-fighting benefits of the prebiotics and the implications for both human and animal health, such research could also yield economic benefits for farmers.