Differentiation of L . interrogans and L . borgpetersenii serovars by ClinProTools software. “2D Peak Distribution View” displaying the distribution of the different 15 serovars (by way of example, 5 replicates per serovar are shown) analysed on the basis of the first two best discriminating peaks among the spectra of all serovars considered. The symbols represent the ratio area/intensity with respect to the two peaks considered for each spectrum, the same symbols represent replicates of the same serovar and the ellipses represent the standard deviation within the same serovar.