Journal of University of Duhok.,Vol. 22, No.2(Agri. and Vet. Sciences),Pp 196-209, 2019(Special Issue) The 3 rd International Agricultural Conference, 2 nd -3 rd October 2019, Duhok 196 IMPACT OF VARIOUS LEVELS OF MEDICINAL PLANTS ON SOME PRODUCTIVE AND PHYSIOLOGICAL TRAITS IN BROILER CHICKENS NECHIRVAN H. ARTOSHI, IHSAN T.TAYBE * and BÜNYAMIN SÖĞÜT ** * Dept. of Animal Production, College of Agricultural engineering science , University of Duhok, Kurdistan Region–Iraq ** Dept. of Animal Science, Faculty of Agriculture, Bingol University, Bingol, Turkey (Accepted for Publication: October 21, 2019) ABSTRACT A study aimed to evaluate the influence of using three medicinal plants on some productive and physiological traits of broiler chickens. Two hundred eighty-eight chicks (Ross 308) randomly distributed into eight groups with three replicates in each treatment. First group was fed the basal diet, without any plant supplement, as control group, while the 2 nd and 3 rd groups were fed the same diet with thyme (5 and 10 g/kg, respectively), the 4 th and 5 th groups were fed diets with Adiantum (3 and 5 g/kg, respectively) and the 6 th and 7 th groups were fed diets supplemented with rosemary at 5 and 10 g/kg, respectively, the combination of plants (7.5 g/kg of thyme and 7.5 g/kg of rosemary and 4 g/kg of adiantum) added to the basal diet of group 8 th . The active compounds of the three plants were analyzed by Gas Chromatography/Mass Spectrometry. Live body weight was measured at weekly intervals. At the end of the experiment, the following traits were measured: carcass traits, internal organ, lymphoid organs and meat color. The obtained results summarized as follows: Fourteen, Fifteen and Twenty-one compounds were identified in the Thyme, Adiantum and Rosemary samples, respectively, and the major compounds were carvacrol (60.77%), gamma-terpinene (41.23%) and α-Pinene (51.87%), respectively. Overall, there is a significant effect of medicinal plants on live body weight in both genders, in which the male chicks in the 4 th group and female chicks in 7 th group had significantly higher live body weight. Regarding male chickens, T2, T3 and T8 groups have significantly higher carcass yield, also each of dressing percentage, breast, legs and wings were higher in T3 group. Furthermore, neck and back weight was higher in T3 group in both genders. It can be concluded that the supplementation of medicinal plants to broiler´s diet had a beneficial effect on most of broiler performance, particularly in male chickens that fed T3 group (Thyme 5g/kg). KEY WORDS: Thyme, Adiantum, Rosemary, Performance, Physiology, meat color, broiler. https://doi.org/10.26682/cajuod.2020.22.2.22 INTRODUCTION atural feed additives of plant origin are generally believed to be safer, healthier and less subject to hazards. Medicinal plants and their products are used in broiler diets or through drinking water in which their beneficial effects as phytogenic feed additives have been proven (Soltan et al. 2008 and Dalkiliç et al. 2009). Herbs have been identified to improvement antimicrobial, antiviral, and antioxidative activities and to sitmulate the immune and endocrine systems (Dahiya et al. 2006). Besides, scientists recently observed that the stimulating and appetizing activity of herbs and plant extracts on poultry digestive and immune system could be benefit health and performance of poultry farms (Gollnisch and Halle 2001; Tucker 2002b). Using medical plant including thyme, rosemary and adiantum in broiler diets could have many effects to broiler performance and health like as enhancing digestion system throughout stimulation of endogenous enzyme (Brugalli, 2003), having autoxidation properties, antimicrobial activities of due to their phytochemical components (Lee et al. 2004b; Dorman and Deans 2000). Thyme (Thymus Vulgaris) is one of the Lamiaceae family (Mikaili et al. 2010). Also it has used for many medicinal purposes: antimicrobial, antinociceptive, respiratory diseases and etc. (Demir et al. 2008). The main phenolic N