Comparing antibacterial effect of different extracts of chicory (Cichorium intybus L.) and its effects on nutrient digestibility and gastrointestinal microflora population in broiler chicks exposed to heat stress

This experiment was conducted to investigate the effect of chicory extract in the diet of broiler chicks in a completely randomized design with 5 dietary treatments, 4 replicates of 20 broiler chicks (1 d old) in each. Treatments consisted of a corn diet - soy as a basal diet (control) and basal diet containing three levels of 150, 250 and 350 mg ethyl acetate extract of chicory per kg and probiotic the recommended amount per kilogram of feed. Chicory was extracted using four different solvents (chloroform, ethyl acetate, methanol and water) and the most effective extracts in vitro antibacterial properties were determined by disk diffusion method and by measuring the diameter of inhibition zone. The most antibacterial effect against E.coli was observed to the ethyl acetate extract. Effects of ethyl acetate extract were investigated on nutrient digestibility and microbial population of the gastrointestinal tractof broilers under heat stress. To determine the digestibility of dry matter, crude protein and crude fat feed sampling and ileum with chromium oxide marker was used. The results showed that the use of the chicks chicory extract reduced the number of E. coli bacteria and increase the number of lactobacilli in the digestive tract. Digestible of protein and fat under the influence of chicory extract showed a significant increase. In the digestibility of dry matter in different treatments were not affected by treatments (P