Journal of Pure and Applied MicrobiologyVol. 9 No. 3

Antibiogram and Multiple Antibiotic Resistance index of Salmonella enterica isolates from Poultry

Jangsher Ali Khan, Irfan Ahmad Mir, S.S. Soni and Sunil Maherchandani

Department of Veterinary Microbiology and Biotechnology, College of Veterinary and Animal Science, Rajasthan University of Veterinary and Animal Science, Bikaner - 334 001, India.

Received on 09 April 2015 and accepted on 16 June 2015



Antimicrobial resistance analysis by 16 different antibiotics was done on 24 isolates of Salmonella enterica belonging to six different serotypes viz S. Virchow (1), S. Heidelberg (5), S. Kentucky (1), S. Agona (1), S. Haifa (14) and two rough strains. The results revealed that the Salmonella isolates were sensitive to ciprofloxacin, chloramphenicol and norfloxacin, nalidixic acid and co-trimoxazole, co-trimazine, gentamicin, amikacin and streptomycin and cephalexin in the decreasing order of frequency. All the strains were found resistant to ampicillin and 75% isolates were resistant to nitrofurantoin and colistin. Twenty isolates exhibited multiple drug resistance against 3 to 9 antibiotics with Multiple Antibiotic index ranging from 0.06 to 0.56. MAR index of 0.37 was found in maximum number of isolates (8) which were resistant to six different antimicrobials. The dendrogram based on resistotyping pattern differentiated 24 isolates into 19 resistance patterns (resistotypes) indicating the validity of this test for differentiating the strains to a level of 97.8%. All 24 Salmonella isolates revealed 65.9% average genetic similarity and level of similarity ranged between 20% to 100%.

Keywords : Antimicrobial-resistance, Salmonella, Multiple Antibiotic Resistance Index, Dendrogram, Resistotypes.