Alarm bells are now ringing, as more and more multidrug resistant bacteria are emerging, several of which pose a major threat for animal and human health. To mitigate this problem, new and effective alternatives for antibiotics should be developed. Lactoferrin is a protein with antimicrobial, proteolytic and immune modulating activities and could be used to reduce antibiotic usage in food-producing animals, like pigs. Especially during the postweaning period, antibiotics are extensively used to control bacterial infections in piglets. In this project, we will unravel the mechanisms via which lactoferrin can improve the gut health of piglets upon infection with enterotoxigenic E. coli. First, we will compare the antimicrobial and proteolytic activity of bovine lactoferrin with native and recombinant porcine lactoferrin. Second, we will compare the immune-modulating activity of these lactoferrins. As lactoferrin, via interaction with its receptors, is translocated to the nucleus of intestinal epithelial cells, it might impact on their gene expression and ultimately influence the response of the host’s intestinal immune system towards pathogens. Finally, a proof of concept experiment will allow us to evaluate the potential of lactoferrin to improve gut health in the context of postweaning diarrhea in piglets. This might allow a reduced use of antibiotics in the swine industry, which would be advantageous for animal as well as human health.