The influence of age and sex on carcass composition, digestive system morphometry and leg bone dimensions in Japanese quail

Japanese quails are birds that are mainly reared for meat and egg production. Early sexual maturity and a high reproduction rate have contributed to the development of this poultry sector. This study investigated the effects of age, sex, and their interactions on the carcass composition, digestive system morphometry, and leg bone dimensions. The research was conducted on 40 Japanese quails: 20 birds at 6 weeks of age (10 males and 10 females) and 20 birds at 52 weeks of age, at the end of the egg production period (10 males and 10 females). Post-slaughter, body weight and the relative proportions of carcass components were recorded. Additionally, the lengths and diameters of intestinal segments, their proportions relative to total intestinal length, and morphometric measurements of the femur and tibia were assessed. The results showed that age significantly affected body weight, with older quails weighing more (174.30±23.59 g) than younger ones (166.94±10.25 g; p<0.05). Also, age significantly influenced the percentage of leg muscles, as well as the relative weights of the gizzard and spleen, and several morphometric parameters of the tibia and femur. Sex had a significant effect, too. Females exhibited higher body weights than males (177.49±26.95 g vs. 163.75±8.41 g) along with changes in selected osteometric dimensions of the tibia and femur. Some traits showed interaction effect. Overall, both age and sex significantly influence carcass composition and selected morphometric characteristics of the femur and tibia, while body weight increases with age and the relative proportion of leg muscles decreases.