Molecular characterisation and serotyping of Pasteurella multocida isolates from Asiatic elephants (Elephas maximus)

Abstract

We report the cultural and molecular characterisation of Pasteurella multocida isolates recovered from Asiatic elephants at Bandipur tiger reserve forest in Karnataka state, India. The forest had witnessed consecutive droughts from 2010 to 2012 and sudden heavy monsoon rains in 2013. Twenty-three elephants died during this period of heavy rains between May and July 2013. Postmortem conducted on a fresh elephant carcass revealed hemorrhagic tracheitis, haemorrhages on heart and lesions of acute septicaemia in all other vital organs. In seven elephant carcasses where fresh samples were not available, bone marrow samples of femur bones were aseptically collected. Heart blood and spleen samples collected at postmortem and two out of seven bone marrow samples yielded the growth of P. multocida. The isolates were typed as P. multocida type B. The phylogenetic analysis of the isolates was carried out by 16S ribosomal RNA (rRNA) gene-based PCR and sequencing of 1.3 Kbp nucleotides on the 16S rRNA gene of the isolates. The isolates showed highest sequence identity with P. multocida isolates of bovine and caprine origin. This is the first report of molecular study on P. multocida from Asiatic elephants.