Fig. 6

Differential FTIR spectral analyses. The second derivate, vector-normalised average spectra were calculated from CE of re-isolated A. pleuropneumoniae Serotype 2 from the left and right tonsil of the infected pig 4 (I4) and the lung of the infected pigs 1–4 und 6 (I1-4 and I6), respectively. The average spectrum of the lung of I1-4 and 6 was subtracted from the average spectrum of the tonsils of I4. Most pronounced differences could be detected in the frequency area of 1800–900 cm⁻¹ and can be related to the protein region (1800–1500 cm⁻¹) and the carbohydrate region (1200–900 cm⁻¹)