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.

This study investigated the effect of adding watermelon juice, vitamin Eselenium and vitamin C to the drinking water on growth performance, internal organs’ weight, and prececal nutrient digestibility in broilers under heat stress. Two hundred and fifty Hubbard F15 day-old broilers were allocated to five treatments with five replicates of 10 broilers per each replicate, based on a completely randomized design. The birds in the control treatment did not receive any supplement in drinking water and reared in thermoneutral temperature. Birds in the other four treatments received watermelon juice at 60% or 30%, vitamin C at 50 mg/L, or vitamin E-Selenium at 1 mL/L of drinking water during the heat stress period. Heat stress applied for 9 hours from day 12 onward. Results indicated birds that received 60% watermelon juice had similar body weight and feed intake compared to control birds. The relative weight of proventriculus, intestine length, and prececal dry matter nutrient digestibility was significantly higher in 60% watermelon juice treatment than other treatments. It is concluded that watermelon juice supplementation at 60% concentration into the drinking water could improve the performance of birds reared under heat stress as a result of restoring water and feed intake and also better prececal dry matter digestibility.

This study examined the effect of dietary supplementation of Kigelia pinnata (KPL) and Plukenetia conophora (PCL) leaves in comparison with oxytetracycline (OXY) and butylated hydroxyanisole (BHA) on growth performance, selected blood biochemical parameters, caecal microbiota, splenic interleukins (IL), serum immunoglobulins (Ig), carcass traits, meat quality, and oxidative stability in broiler chickens. One day old Arbor Acres chicks (n=420) were randomly assigned to either basal diet only (BD); basal diet + 0.5 g/kg oxytetracycline + 0.12 g/kg BHA (OXYBHA); basal diet + 1 g/kg KPL (KPL-1); basal diet + 2 g/kg KPL (KPL-2); basal diet + 1 g/kg PCL (PCL-1); or basal diet + 2 g/kg PCL (PCL-2) for 42 d. Each dietary treatment had seven replicates with 10 chicks per replicate. Supplemented birds gained (P < 0.05) more weight and had a better feed conversion ratio compared with the BD birds. Hematological indices, IL-1β, and IL-6 did not differ among the treatments. BD birds had lower (P < 0.05) carcass weight and IL-10, and higher (P < 0.05) IgG, IgM, Salmonella spp., and E. coli counts than the supplemented birds. The KPL-2 birds had the least (P < 0.05) E. coli and Salmonella spp. counts and IgM among the supplemented birds. Lactobacillus spp. count was lower (P < 0.05) in OXYBHA birds compared with KPL and PCL birds. Carbonyl and malondialdehyde contents in the Sartorius muscle, and drip loss and carbonyl content in the Pectoralis muscle of the BD birds were higher (P < 0.05) than those of the supplemented birds. These results illustrate that the 2 g/kg KPL and 2 g/kg PCL could be used as an antioxidant and an antimicrobial in the diets of broiler chickens.