Abstract: Mannheimia sp. and P. multocida (Pm) strains were isolated from pneumonic lungs (n = 475) which were obtained in two slaughterhouses in Mexico. Isolation and phenotyping were carried out by means of in vitro culture, as well as biochemical and immunological tests. Of the 131 isolates 60.3% was Pm and 39.7% was Mannheimia sp. The isolating rate in lungs was 16.6% for Pm, 10.7% M. haemolytica (Mh) and 0.2% M. glucosida (Mg) in both slaughterhouses. These differences were significant (p 0.05). Out of 52 Mannheimia sp. isolations, 98% was Mh and 1.9% Mg. Out of 51 Mh isolates 33% was of Serotype 1(S1), 17.6% S6 and 49% Non-Typable (NT). These differences were significant (p 0.05). Out of 79 Pm isolations, 98.7% was biotype A and 1.2% biotype D. These differences were significant (p 0.05). Pm got the highest rate of isolations in lungs which differs from data of previous results where Mh is considered as the most pathogenic bacteria and the most commonly associated to bovine pasteurelosis pneumonic. The highest frequency of Mh S1 and Pm biotype A confirms that these two bacteria are the most commonly found in pneumonic lungs in Mexico.
C.J. Jaramillo-Arango , R. Hernandez-Castro , V.Campuzano-Ocampo , F. Suarez-Guemes , R. Delgado-Gonzalez and F. Trigo-Tavera , 2007. Characterisation of Mannheimia Sp. and P. multocida Strains Isolated from Bovine Pneumonic Lungs in Two Slaughterhouses in Mexico. Journal of Animal and Veterinary Advances, 6: 1398-1404.