In suckling pigs, weaners and fattening pigs respiratory diseases appear consistently. To determine the etiology and the number of animals to be examined, the clinical symptoms of the sick pigs of each age group and an estimated value of the percentage of potentially affected pigs in the population should be detected first. The diagnostic method must match the age group and lung pathogens should be present in the organs of the respiratory tract. On the basis of one case study per age group, the possible diagnostic methods and their transfer into practice are presented separately for suckling pigs, weaners and fattening pigs. It will be taken into account that not every diagnostic method suits every age group equally. Furthermore, diagnoses are assessed which lead to different measures for different age groups of the animals.
