The current research was conducted to compare growth, carcass traits, pH, intramuscular collagen (IMC) properties, and genetic bases of IMC and carcasses (breast-muscle weight) of different lines and generations of adult males and females of Japanese quail (Coturnix japonica). Forty-four quails (generation F0), 22 Pharaoh (F-33) meat-type males and 22 Standard (S-22) laying-type females, were crossed to produce the F1 hybrids generation. The F2 generation was created by mating one F1 male with one F1 female, full siblings. The birds, randomly chosen from F0 (22 males and 22 females), F1 (22 males and 22 females), and F2 (84 males and 152 females) were raised to 20 wk of age in collective cages. Quails were fed ad libitum commercial diets. At slaughter, all birds were individually weighed (after a fasting period of 12 h) and dressing yield (without giblets) was calculated. The carcasses were then dissected. Genomic DNA was extracted from all of the blood, and 30 microsatellite markers located on 2 quail chromosomes were genotyped. The F -: 33 quails had higher in vivo and postmortem performances and a higher abdominal fat percentage than those of the egg line. Meat from S -: 22 quails had a slower collagen maturation (hydroxylysylpyridinoline crosslink/collagen) and a higher ultimate pH. The F1 and F2 generations showed an evident sexual dimorphism, and an additional effect could be due to hybrid heterosis evident in F2. Meat from quails of F1 and F2 generations had a lower IMC amount with a higher degree of collagen maturation compared with parental lines. Two statistically significant QTL have been detected on quail chromosome 2 (CJA02): a QTL with an additive effect (0.50) for IMC in the marker bracket GUJ0037 and GUJ0093; a second QTL with additive (1.32) and dominant (1.91) effects for breast-muscle weight in the marker bracket GUJ0084 and GUJ0073. To our knowledge, this is the first report of a QTL associated with breast-muscle weight and IMC in quail and poultry species, respectively.

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The effect of intramuscular injections of vitamin E on growth, carcass traits, intramuscular collagen (IMC) characteristics and decorin of growing lambs was studied. A total of 24 15-day-old Ile de France suckling male lambs were divided into two groups and weekly intramuscular injections of DL-α-tocopheryl acetate (control group, 0 IU; Vitamin E treatment, 150 IU) were given until the lambs were 64 days old. Lambs were individually weighted at 15, 29, 43, 57 days of age and at slaughter (71 days old). Dry matter intake and average daily weight gain were recorded. Hot and cold carcass weights were recorded and dressing percentages were calculated after dressing and chilling (2°C to 4°C for 24 h). Carcass shrink losses were calculated as well. Longissimus muscle (LM) pH and area were measured. The pelvic limb was removed and its percentage was calculated based on cold carcass weight. IMC and decorin analyses were assessed on LM and semimembranosus muscle (SM). DL-α-tocopheryl acetate treatment reduced ( P < 0.05) collagen maturity and increased ( P < 0.05) decorin in both LM and SM muscles of growing lambs, while it did not affect IMC content. In addition, vitamin E did not influence growth, carcass weight, dressing percentage, carcass shrink losses and area of LM but decreased ( P < 0.05) the pelvic limb percentage. The LM pH values were higher ( P < 0.05) in vitamin group than in control group. Furthermore, different IMC characteristics between the muscles ( P < 0.01) were apparent. Multiple intramuscular injections of DL-α-tocopheryl acetate influence extracellular matrix in lambs, which could affect meat tenderness.