Antimicrobial effect of Zataria multflora, Thymus daenensis, Althea officinalis, and Urtica dioica on growth of Escherichia coli isolated from poultry colibacillosis

In order to study the antibacterial effect of Zataria multflora، Thymus daenensis، Althea officinalis، and Urtica dioica، chicken Escherichia coli (E. coli) isolates sensitive to enrofloxacin (ENR)، Sulfadimidin-trimetoprim (Sul-trim)، Florfenicol (FLO)، Flemequine and Gentamycin were used. After the preparation of extracts from herbal plants، the antibacterial sensitivity of herbal plants with different concentrations (100، 50، 25، 12. 5 and 6. 25%) was assayed by disc diffusion test. Also، propylene glycol as negative control and commercial antibacterial drugs comprising ENR، Sul-trim and FLO as positive control were used and compared with herbal plant extracts for antibacterial sensitivity. The results showed maximum growth inhibitory diameter for E. coli induced following usage of florfenicol، 100% and 50% concentration of Zataria multflora and، Thymus daenensis extracts، respectively. The 50% and 100 % concentrations of Althea officinalis، and Urtica dioica extracts could induce growth inhibitory diameter the same as ENR and Sul-trim. The overall، results showed Zataria multflora، Thymus daenensis، Althea officinalis، and Urtica dioica have degrees of antibacterial effect and these herbal plants can be used as an antibacterial supplement in the treatment of avian colibacillosis. Therefore، the phytochemical analysis for complementary study is necessary.