The Effect of Two Thyme Species Hydroalcoholic Extract on Nutrient Digestion and Antioxidant Status of Broiler Chickens

The effect of two thyme species hydroalcoholic extracts and flavomycin on nutrients digestibility and antioxidant status of male broilers was assessed in a 42-day trial using 128-day-old Ross 308 chicks by employing a completely randomized design with four treatments and four replicates. The experimental treatments consisted of control, 0.05 percent Thymus daenensis extract, 0.05 percent T. kotschyanus extract and 0.1 percent flavomycin. Throughout the experiment, the chickens on flavomycin diet had a better weight gain and feed conversion ratio (P<0.05). Although thyme diets had no effect on weight gain, the birds on diet containing T. daenensis extract had better feed conversion ratio than those on the control diet (P<0.05). The jejunal villus height and villus height to crypt depth ratio increased in birds fed with diets containing T. daenensis extract and flavomycin (P<0.05). However, villus surface area of jejunum was increased in birds on diets containing the additives (P<0.05). Feeding chickens with diets containing T. daenensis extract and flavomycin decreased the thickness of muscle layer of jejunum (P<0.05). Digestibility of dry matter and organic matter was increased by T. kotschyanus extract and flavomycin (P<0.05).Nitrogen retention was increased in birds fed with all additives (P<0.05). The activity of blood superoxide dismutase and glutathione peroxidase in birds receiving thyme extract was higher than those of the control group (P<0.05). Malondialdehyde of thigh meat declined in birds receiving diets containing T. kotschyanus extract in comparison with other treatments (P<0.05). Based on the results of the study such as improved feed conversion ratio, intestinal mucosal morphometry and body immune status parameters, application of 0.05 percent T. daenensis extract can be suggested as a growth promoter in broiler diets.