Health monitoring of swine maternities mostly rests on analysing the serum for detecting antibodies against important pathogens, like those causing porcine pleuropneumonia (Actinobacillus pleuropneumonia, or “App”), porcine reproductive and respiratory syndrome (PRRS virus) and enzootic pneumonia (Mycoplasma hyopneumoniae, or “Myco”). However, blood withdrawal requires skilled staff and can even be dangerous for both the animal and staff. In sows, colostrum withdrawal is an interesting alternative: antibodies are also present in colostrum, and withdrawal is easy and harmless for the sows and staff. It can be done more often, for faster disease detection. Also, colostrum can be frozen immediately without any treatment. Preparation requirements before serological analysis of colostrum as well as the sensitivity and specificity of this analysis in detecting the above-mentioned infections have been examines. It has been found that simple centrifugation of colostrum followed by removal of the fat layer was a sufficient preparation. For the detection of “App” (with an ELISA LC-LPS test) and “Myco” (with ELISA from Dako company), the same dilution for colostrum as for serum can be used. However, for detecting PRRS and “Myco” using an ELISA test from IDEXX Laboratories, dilution must be, respectively, between 1/40 and 1/100, and 1/120. The optimal withdrawal period of colostrum is from 6 hours before to 18 hours after farrowing, and colostrum can be stored at least 60 days in the freezer. Validation with positive and negative herds proved the serological analysis of colostrum to be as specific and sensitive as that of serum for detecting those three infections.