Here we present the work of the multidisciplinary consortium IRAS (Development of Genetic Markers for Immune Defence and Resistance in the Porcine Respiratory Tract) which includes different commercial and research institutions and was formed as a response to the call "Functional Genome Analysis in the Animal Organism (FUGATO)" by the German Ministry of Education and Research. IRAS started work in the fall of 2005 and--using the experimental infection of pigs with Actinobacillus pleuropneumoniae as model pathogen--aims at i) characterizing the course of infection by clinical as well as advanced laboratory tools (phenotypic-genetic approach) and ii) defining the diversity and distribution of allels known to be associated with immune defence in mouse and man (homolog-genetic approach). The intention is to identify genetic markers for increased resistance to infection thereby providing additional tools for the estimation of breeding values to the pig industry.