Comparative pathogenicity of Listeria isolates

Abstract

The pathogenic potential of 30 Listeria spp. isolates from female reproductive disorders in buffaloes, cows, goats and sheep were tested in mice and guinea pigs. The infected mice that succumbed to infection during 2-5 days were mostly identified as L. monocytogenes and whereas those identified as L. ivanovii died during 7-13 DPI. The infected mice that did not succumb to infection were sacrificed one each on 13th and on 20th DPI and invariably were L. grayi, L welshimeri and L. innocua. All the mice were subjected to necropsy, the intensity of gross lesions on liver, spleen and heart comprised congestion, haemorrhages and scattered necrotic foci. The histopathological investigations of these tissues confirmed the gross lesions. The reisolation of the organisms from infected mice were invariably successful.