In this study 120 weaned female piglets were clinically examined and porcine C-reactive protein (CRP) concentration determined in blood serum by means of a competitive enzyme ligand assay. CRP values were put into relation to clinical (catarrh, diarrhoea, inflammation and fever) and pathomorphological findings. It was found, that CRP values are clearly elevated during infections with fever and inflammatory processes, but not in the case of catarrh and diarrhoea. The pathomorphological investigations of some animals with clinical findings revealed changes in lungs, bowels and liver. Special attention has to be paid to the fact that, as in man, CRP is an acute phase reactant, and therefore a sensitive, but non-specific indicator for infections and inflammation processes. Serum CRP screening seems to be a good means for the supervision of the general state of health in pigs.