Microscopic changes in the kidneys of cows infected with Leptospira sp.

The article presents data on histopathological studies of the kidneys of cows, which either recovered or died from leptospirosis. Fragments of seven kidneys from slaughtered cows, positive for Leptospira antibodies in the microscopic agglutination test (MAT) (titres of 50 and higher) were used in the study. The MAT was conducted with eight serological groups of Leptospira: Canicola, Grippotyphosa, Hebdomadis, Icterohaemorrhagiae, Pomona, Sejroe, Tarassovi, and Australis. Microscopic changes in all morphological structures of the kidneys were presented. Micromorphological criteria, which can be used for post-mortem diagnosis of leptospirosis were established. They included: serous glomerulonephritis with granular dystrophy of podocytes, necrosis and collapse of the inner layer of Bowman's capsule, partial destruction of capsule and vascular glomeruli, granular and vacuolar degeneration and destruction of tubular epithelial cells, foci of interstitial oedema, and infiltrations predominantly with monocytes and isolated neutrophils. Microscopic changes in the kidneys suggest that the cows died from leptospirosis as a result of toxic shock syndrome.