Effects of Olive Leaves Extract and Olive Oil on Growth Performance, Nutrient Digestibility and Ileum Morphology of Japanese Quails

The present study was conducted to determine the effects of olive extract leaf and olive oil on growth performance, nutrient digestibility, carcass characteristics and intestinal morphology in Japanese quail. A total of 528 Japanese quail chicks 1-days-old were allocated to 6 treatments group with 4 replicates each containing 22 birds. This study was performed in a 2×3 factorial experiment with completely randomized design. Experimental treatments were included two levels of olive leaf extract (0, and 400 mg/kg) and three levels of olive oil (0, 2.5 and 5%). The results was revealed that the average daily weight gain were significantly increased in diet containing 5 % of olive oil compared to control group (P<0.05). The diet containing 2.5 percent olive oil decreased average daily feed intake as compare to control diet (P<0.05). The ileum  histomorphometry showed that crypt depth and height villus to crypt depth ratio in birds received 2.5 and 5% olive oil decreased and increased compared with control group, respectively (P<0.05). The results showed that the apparent digestibility of protein, ash, fat, phosphorus and energy in the control group was significantly lower than other treatments (P<0.05). The apparent digestibility of fiber was higher in the treatment containing 5% olive oil and the treatment containing 400 mg/kg diet of olive leaf extract (P <0.05). Diet containing 5% olive oil had the highest metabolizable energy compared to the other experimental groups (P <0.05). In conclusion, the findings of this study suggests that dietary inclusion of olive oil up to 5 percent had benefit effects on quail production indices.