摘要：Summary Due to its antioxidant properties, ability to improve taste of feed, digestion function and to boost immune response, phytogens, which include essential oils and their components, have a great potential for use in broiler fattening. Furthermore, because of its antimicrobial properties they could be used as a natural and acceptable replacement for antimicrobial growth promoters. Before the considerable use of phytogens in broiler fattening, the mechanism of its action, compatibility with other feed components, safety and toxicological assessment should be explored more detailed. Despite the fact that phytogens can be applied in poultry production, breeders are still not well informed about their use. The positive effect of oil extract of thyme (thymol and carvacrol) and cinnamon (cinnamaldehyde) added to the chickens feed (at 100 and 200 ppm) demonstrated improved weight gain, feed intake and feed conversion. In addition, larger quantities of essential oils in feed, significantly affected feed conversation ratio, abdominal fat and internal organs percentage (liver, heart and gizzard), while treatments with essential oils of thyme and cinnamon significantly reduced cholesterol and H/L ratio, and raised erythrocytes count (RBC), PCV, Hb and white blood cell count (WBC) compared with the control group. On the international level is necessary to standardize commercially available components of essential oils to improve their everyday use.
关键词：broilers; essential oils; production performances; growth promoters
