Histopathological analysis of granuloma encapsulation in asymptomatic cattle naturally infected with

<p><b><i>M. bovis.</i></b> (<b>A</b>) Granulomas were formalin-fixed, paraffin-embedded and 4 µm-sections Massońs trichrome stained, categorized and scored according to their intensity of encapsulation of primary granulomas into three levels: (1 and 2) I, thin encapsulation; (3 and 4) II, dense fibrous capsule; and (5 and 6) III, thickly fibrous encapsulation. (A, inset) Acid Fast-Bacilli (AFB). (Left panels, slides shown at 10× magnification; Scale bar = 100 µm. Right panels, slides shown at 40× magnification; Scale bar = 50 µm. Inset, slides shown at 100× magnification. Correlation between intensity of granuloma encapsulation with mycobacterial loads (<b>B</b>) or gross pathology severity score (<b>C</b>) in cattle naturally infected with <i>M. bovis</i> are presented. Spearman’s correlation indexes (Spearman’s r and p values) are shown in the graphs.