University of Guilan Animal Production Research 2252-0872 6 4 2018 02 20 Effect of different levels of Salvia mirzayanii essential oil on performance, some blood and immunity parameters of broiler chickens under heat stress conditions Effect of different levels of Salvia mirzayanii essential oil on performance, some blood and immunity parameters of broiler chickens under heat stress conditions 69 80 2756 10.22124/ar.2018.2756 FA S. Bayati MSc. Graduated Student, Animal Science Department, Ramin Agriculture and Natural Resources University, Mollasani, Ahwaz, Iran S. Salari Associate Professor, Animal Science Department, Ramin Agriculture and Natural Resources University, Mollasani, Ahwaz, Iran A. Tatar Assistant Professor, Animal science department, Ramin Agriculture and Natural Resources University, Mllasani, Ahwaz, Iran M. Sari Associate Professor, Animal Science Department, Ramin Agriculture and Natural Resources University, Mollasani, Ahwaz, Iran Kh. Mirzadeh Associate Professor, Animal Science Department, Ramin Agriculture and Natural Resources University, Mollasani, Ahwaz, Iran Journal Article 2016 12 02 An experiment was conducted to evaluate different levels of <em>Salvia mirzayanii</em> essential oil on performance, blood and immunity parameters of broiler chickens under heat stress condition. Completely randomized design with four treatments (0, 150, 300 and 450 ppm of <em>Salvia mirzayanii </em>essential oil) was used for 42 days. Broilers were under heat stress conditions from 22 days of age. Increasing levels of essential oil in the diet significantly decreased feed intake in comparison with the control at the starter period. But level of 450 ppm essential oil had the highest feed intake during grower period and total of experiment. Feed conversion ratio significantly decreased by increasing levels of essential oil compared with the control. Triglyceride and LDL cholesterol concentration were significantly decreased at the level of 450 ppm essential oil. Percentage of heterophile, heterophil/lymphocyte ratio (H/L) decreased, and percentages of lymphocyte and monocyte increased by increasing levels of essential oil at 21 days of age (<em>P</em><0.05). But there was not significant difference between treatments after heat stress at 42 days of age. Bursa of Fabricius weight was the highest at the level of 450 ppm essential oil (<em>P</em><0.05). Gastrointestinal tract and gizzard weight significantly increased at the level of 150 ppm essential oil (<em>P</em><0.05). Abdominal fat weight significantly decreased at the level of 450 ppm essential oil. Highest percentage ash of tibia was observed at 450 ppm essential oil (<em>P</em><0.05). According to the results of this experiment, the use of <em>Salvia mirzayanii</em> essential oil up to 300 ppm in broiler nutrition under heat stress was recommended. An experiment was conducted to evaluate different levels of <em>Salvia mirzayanii</em> essential oil on performance, blood and immunity parameters of broiler chickens under heat stress condition. Completely randomized design with four treatments (0, 150, 300 and 450 ppm of <em>Salvia mirzayanii </em>essential oil) was used for 42 days. Broilers were under heat stress conditions from 22 days of age. Increasing levels of essential oil in the diet significantly decreased feed intake in comparison with the control at the starter period. But level of 450 ppm essential oil had the highest feed intake during grower period and total of experiment. Feed conversion ratio significantly decreased by increasing levels of essential oil compared with the control. Triglyceride and LDL cholesterol concentration were significantly decreased at the level of 450 ppm essential oil. Percentage of heterophile, heterophil/lymphocyte ratio (H/L) decreased, and percentages of lymphocyte and monocyte increased by increasing levels of essential oil at 21 days of age (<em>P</em><0.05). But there was not significant difference between treatments after heat stress at 42 days of age. Bursa of Fabricius weight was the highest at the level of 450 ppm essential oil (<em>P</em><0.05). Gastrointestinal tract and gizzard weight significantly increased at the level of 150 ppm essential oil (<em>P</em><0.05). Abdominal fat weight significantly decreased at the level of 450 ppm essential oil. Highest percentage ash of tibia was observed at 450 ppm essential oil (<em>P</em><0.05). According to the results of this experiment, the use of <em>Salvia mirzayanii</em> essential oil up to 300 ppm in broiler nutrition under heat stress was recommended. https://ar.guilan.ac.ir/article_2756_936c1a3a4059a7c3502d7083f494e8cd.pdf