effects of thyme leaves powder and it's essential oil on performance, meat quality and intestinal characteristics of meat type quails

this experiment was conducted to investigate the effect of thyme essential oil and powder in comparison to antibiotic on performance of meat type quails, in a completely randomized design with 6 treatments, 4 replicate. the dietary treatments consisted of the basal diet without any added compounds (control), 100mg virginiamycin/kg, 0.1 or 0.2% thyme powder and 100 or 200 mg thyme essential oil/kg. the measurement parameters included performance, meat quality, morphology and microbiology of intestine. supplementing 0.1% powder thyme and virginiamycin increased body weight gain of quails at d 0 to 35. thyme powder and essential oil caused reduction in thiobarbituric acid, dripping loss and cooking loss and increased water holding capacity. the highest counts of lactobacilli bacteria, belong to thyme treatment (except for 200 mg essential oil/kg) and the lowest of it has been seen in antibiotic ones and the lowest count of coliform bacteria belonged to antibiotic treatment. maximum length and width of the villi and minimum depths of crypts was observed in thyme treatments (except for 200 mg essential oil/kg). in antibiotic treatment, crypt depth was significantly increased in addition to increase of length and width of the villi.