Antibacterial Activity of Essential Oil of Aeollanthus pubescens on Multidrug Resistant Strains of Salmonella and Escherichia coli Isolated from Laying Hens Farming in Benin

Abstract

Infections due to Escherichia coli and Salmonella are of the major constraints for the laying hen’s industry as they cause mortality and serious economic losses. The use of conventional antibiotics to control bacterial has shown limits because it allows multidrug-resistance. The main objective of this study was to assess the antibacterial activity of essential oil from Aeollanthus pubescens on multidrug resistant strains of Salmonella and Escherichia coli isolated from laying hens faming in the department of Atlantique in Benin. Altogether, 11 strains of Salmonella and 16 strains of Escherichia coli have been isolated from 101 samples of different organs including liver, spleen, lung, feces and yolk according to standardized methods and their biochemical profile using API 20E gallery. Test of sensitivity was carried out on 11 antibiotics of six different families on identified strains in order to determine their resistance profile. A sensitivity test was carried out on multi-drug resistant strains with Aeollanthus pubescens essential oil to determine their sensitivity with regard to this essential oil. The results showed that the majority of Salmonella strains presented resistance to Tetracyclines (72.7%) and Sulfonamides (63.6%) and all Escherichia coli strains are resistant to Sulfonamides (100%) followed by Tetracycline (93.75%) and Ampicillin (75%). Aeollanthus pubescens essential oil was active on all the multi-drug resistant strains investigated with Minimal inhibitory concentration varying from 0.41 ± 0 mg/ml to 0.83 ± 0 mg/ml for Salmonella and from 0.41 ± 0 mg/ml to 1.66 ± 0 mg/ml for Escherichia coli (P < 0.001). Besides, the oil can get rid of all the strains of Salmonella and the multi-drug resistant Escherichia coli investigated. Those results provide alternatives to control poultry bacterial pathologies in Republic of Benin. However, disease due to Escherichia coli and Salmonella must be taken more seriously and study on their resistance to antibiotic must be deepened as well.