Effect of Different Levels of Essential Oil of Satureja Hortensis on Performance, Carcass Characteristics and Some Immune and Blood Parameters of Broiler Chickens

This experiment was conducted to evaluate the effect of different levels of Satureja Hortensis essence on performance، carcass characteristics and immune response of broiler chickens. 220 one day old Ross 308 chicks were used in completely randomized design with 20 experimental units with 4 treatments، 5 replicates and 11 chicks in each replicate for 42 days. The dietary treatments consisted of a basal diet، and Satureja Hortensis essence (150، 300 and 450 ppm) added to the basal diet. Performance parameters were recorded weekly and carcass characteristics analyzed at 42 days of age. The results showed that consuming 300 ppm essence increased the feed intake of broiler chickens (P<0. 05). The lowest relative weight of abdominal fat was related to 450 ppm Satureja Hortensis essence (P<0. 05). At 35 and 42 days of age، highest antibody titer against SRBC was observed in group fed with diet containing 150 ppm essence (P<0. 05). At 35 day، highest antibody titer against Newcastle at 150 ppm and at 42 day، the highest antibody titer was observed in group fed diet containing 300 ppm Satureja Hortensis essence. At 42 day، the highest antibody titer against Gumboro was related to 150 ppm essence (P<0. 05). The lowest percentage of heterophil e، the highest percentage of lymphocytes and the lowest ratio of heterophil e to lymphocyte proliferation were observed in the 450 ppm essence (P<0. 05). Our results suggest that addition of Satureja Hortensis essence to broiler diet did not affect performance and carcass characteristics but improved immune responses of broiler chicks.