- - - Department of Clinical Sciences, Faculty of Veterinary Medicine, Shahid Chamran University of Ahvaz, Ahvaz, Iran
- - - Graduate from Faculty of Veterinary Medicine, Shahid Chamran University of Ahvaz - Iran
- - - Department of Clinical Sciences, Faculty of Veterinary Medicine, Shahid Chamran University of Ahvaz, Ahvaz, Iran
- - - Department of Pathobiology, Faculty of Veterinary Medicine, Shahid Chamran University of Ahvaz, Ahvaz, Iran

The recent study was performed to investigate the effects of Antibiofin® (including mostly Thymus vulgaris) in drinking water on intestinal bacterial population in broiler chickens. A total of 120 one day-old broiler chickens were purchased and divided into three equal groups. Each group divided into four subgroup of 10 chicks. Chickens of groups A and B received 0.1% and 0.2% of Antibiofin®, respectively in drinking water from one week before vaccination till two weeks after vaccination. Chickens of group C did not receive Antibiofin®. All groups were subcutaneously vaccinated with AI-ND killed vaccine (subtype H9N2) at neck back site at nine days old. The results of this study showed that the consumption of antibiofin® at 0.1%  and 0.2% concentrations reduced colony forming units of Escherichia coli in group A and B compared to control group, though it was not statistically significant. The colony forming units of Escherichia coli in digesta of ileo-cecum in group A and B on Mac Conkey agar, nutrient agar and Eosin methylene blue agar showed a lower number compared to control group. However, there was no significant difference between all groups in E. coli counts.

Antibiofin®, thyme extract, E. coli, intestine, broiler chickens