Evaluating the Effect of Two Types of Thyme Essential Oils (Zataria Multiflora & Ziziphora Clinopodioides Lam) on Some Productive Traits and Blood Parameters in Broilers

This experiment was conducted to study the effect of thyme extracts from Zataria multiflora and Ziziphora clinopodioides Lam on some productive traits and blood parameters. A total of 240 one-day-old, male broilers of Ross 308 were used in a completely randomized design with 6 experimental groups and 4 replicates with 10 birds in each. Experimental treatments consisted of a basal soybean-meal diet (control), the basal diet supplemented with vitamin E at 200 mg/kg, Zataria multiflora essential oil at 200 mg/kg or 400 mg/kg, and Ziziphora clinopodioides essential oil at 200 mg/kg or 400 mg/kg. The results showed that the birds in the experimental groups consumed more feed and had significantly greater body weight as well as energy and protein efficiency in the whole experimental period, especially Ziziphora clinopodioides at the level of 400 mg/kg, compared to the control group (P < 0.05). Thyme extracts had a significant effect on the most blood factors, except cholesterol and LDL-c (P < 0.05). Thyme extracts significantly reduced serum albumin and improved HDL-c level (P < 0.05). The experimental groups had a significant effect on the relative weight of breast and thigh, malondialdehyde concentration, lipid peroxidation, and antioxidant enzyme activity (P < 0.05). Based on the results, Ziziphora clinopodioides at the level of 400 mg/kg can be introduced as an effective oral additive to improve the studied traits.