The antibacterial activity of alcoholic extract of oak against some yolk sac infection produced by bacteria in broiler chicks

The present study aimed to investigate the antibacterial activity of the graduated concentrations from the alcoholic extract of oak (Quercus acuta). (25, 50, 100, 200 mg/ml) were tested against the growth and multiplication of some pathogenic bacteria causing yolk sac infection in broiler chicks (S. aureus, Streptococcus spp., Salmonella spp. and E. coli) were compared with the effectiveness of ampicillin (10μg), gentamicin (30 μg) and neomycin (30 μg) in culture media, in the same time we also investigate the effect of incubated temperature on the growth inhibition zone of the oak extract through conservation of culture media in two different temperature (25°, 37°C) for 24 hrs with the helping of incubator. The result revealed that the mentioned bacteria showed high sensitivity toward different concentrations of alcoholic extract of oak and this result were close, often, especially at high concentrations. Our result revealed that the activity increased with increase concentration of extract, in the same time we observed that the incubation temperature factor showed significant effects on the results especially with the growth of salmonella and E. coli in culture media.