عنوان مقاله [English]
This study was carried out to evaluate the effects of different levels of dietary metabolizable energy and crude
protein on performance (during 5-24 and 25-38 days of old) and carcass characteristics of Japanese quails. The
experiment was conducted in a 3×5 factorial arrangement in a completely randomized design with four replicates
at each treatment and 40 quails at each replicate. Fifteen diets including three levels of metabolizable energy
(2800, 2900 and 3000 kcal ME/ kg) and five levels of crude protein (22, 23, 24, 25 and 26%) were considered.
On day 41, one hundred twenty birds were slaughtered to access carcass characteristics. No significant
interaction among energy-protein and protein levels on measured characters was observed. During 5-24 days of
old, daily weight gain of quails fed 3000 kcal ME/ kg diet (4.42 g) was higher than the other levels (P< 0.01) and
feed conversion ratio was lower in 3000 (2.90) than 2800 ME (kcal/kg of diet) (3.21) (P< 0.01). During 25-38
days of old, daily weight gain increased (6.16 g) and feed conversion ratio decreased (3.52) with increasing ME
level from 2800 to 3000 kcal ME/ kg (P<0.05). The ME level had not significant affect on feed intake and
carcass, breast and thigh yields. It concluded that using diets containing 3000 kcal ME/ kg and 22% crude protein
is recommendable to achieve a desirable performance in Japanese quails.