Growth of long bones in European and Japanese quail from the 13th day of incubation to day 35 post-hatch.

This study described the growth, morphometric, biomechanical, and chemical properties of the femur, tibiotarsus, and tarsometatarsus of European and Japanese quail. Analyses were performed at 13 and 15 days of incubation, at hatch, and at 4, 7, 10, 14, 21, 28, and 35 days post-hatch (n=6/subspecies/period). Bone specimens were analyzed by cone-beam computed tomography, biomechanical assays, chemical analyses, and histomorphometry. Variables were fitted by the Gompertz function and its derivative or assessed using the analysis of variance. Analysis of the derivative of Gompertz curves showed that the growth behavior of the tarsometatarsal bone was similar between quail subspecies, and the femur and tibiotarsus of European quail increased first in width and then in length, whereas the opposite occurred in Japanese quail. There was an interaction between quail subspecies and days of growth on femoral, tarsometatarsal, and tibiotarsal bone densities. Femoral and tibiotarsal cross-sectional areas were influenced by the interaction of quail subspecies and day of growth. Interaction effects were significant for breaking strength and phosphorus percentage. European and Japanese quail have different femoral and tibiotarsal growth patterns, especially in the first few days after hatching, whereas tarsometatarsal growth is similar between subspecies.

Growth of breast muscles in European and Japanese quail raised in meat production system: a morphological analysis.

Growth curves have been described in the quail but with no attention to the muscle composing of the breast. The description of the characteristics of growth curves to body weight and to breast muscle was the aim of this study. Morphological development of Musculus supracoracoideus and Musculus pectoralis in European and Japanese quail was assessed from the final incubation of to 35 days. Gompertz models were adjusted with maximum growth rates to body weight, breast weight, and Musculus pectoralis and supracoracoideus weight at 17.6; 22.2; 23.5, and 21.4 days. The European quail had a higher body and breast weight at maturity. Musculus supracoracoideus developed faster in both subspecies but with larger Musculus pectoralis. Both musculus had a greater number of fibers type IIA and largest fibers IIB, with quadratically increasing in fiber diameter with age in both subspecies and muscles. At 35 days, results of meat quality indicated similarity between genders and subspecies, with darker and redness breast meat in Japanese quail. In conclusion, breast weight gain was a result of type IIA and IIB fiber hypertrophy in both muscles and, despite the difference in size and aptitude, Japanese and European quail showed similar body and muscle growth patterns.