This study evaluated the effects of feeding varying levels of dietary DL-methionine (MET) supplementation on breast meat (BM) quality of broilers of different sex. The 1-day-old, sexed chicks (Ross 708, 1552) were randomly allocated into four groups (each with 4 replicates) and were raised with diets supplemented with 0, 0.5, 1, or 2 g MET/kg of feed to a common weight (2.72 kg). Color, pH, drip loss (DL), water-holding capacity, moisture uptake, cooking yield (CY), texture, total antioxidant capacity (TAC), and lipid oxidation (LO) were determined using BM samples harvested 24 h postmortem. The male BM had higher redness, TAC, firmness, and toughness but lower yellowness (p < 0.01) than the female BM. In both sexes, birds fed 0.5 g/kg MET had lower DL (p < 0.01) than those fed 1 and 2 g/kg MET. For storage up to 3 days, MET suppressed LO in cooked BM (p < 0.01) and suppression increased as MET increased. CY for 1 and 2 g/kg MET were higher (p < 0.01; 79.04 and 78.60%, respectively) than CY for 0 and 0.5 g/kg MET (66.18 and 68.03%, respectively). These results suggest that MET supplementation at 1 g/kg or higher for broilers can improve oxidative stability, muscle functionality, and breast meat CY.

This study was designed to evaluate the effects of dietary supplemental DL-methionine (MET) on live performance and meat yield for broilers raised to a common weight. A total of 1552 one-day old Ross 708, sexed broilers were randomly distributed to 32 pens resulting in eight treatments (TRT) of four replicates with 44 male or 53 female/pen. A randomized complete block with a 2 × 4 (sex × 4 MET levels 0, 0.5, 1, and 2 g/kg) factorial arrangement of TRT was used. A common weight of 2400 g was approached by day 46 (1 and 2 g MET/kg feed) and day 48 (0 and 0.5 g MET/kg feed). Supplementation of MET at 1, and 2 g/kg had a lower (p < 0.01) feed conversion ratio (FCR) at day 46/48 than broilers fed 0.5 g MET/kg. Broilers without supplemental MET had the worst (p < 0.01) feed conversion and average daily gain (ADG) at day 46/48. Birds fed 0 g MET/kg of feed had lower (p < 0.05) whole eviscerated carcass without giblets (WOG), yield than birds fed 2 g MET/kg of feed. Additionally, birds fed 0 g MET/kg of feed had lower (p < 0.05) breast fillet and tender percent yields than birds fed supplemental MET. Elimination of MET from organic broiler diets resulted in reduced ADG, breast fillet yield and feed efficiency of meat yield of broilers raised to day 46/48. Reduction in MET supplementation below current levels reduced the efficiency of meat production of organic broilers raised to day 46/48.

Coccidiosis impairs broiler performance and meat quality, whereas dietary corn source may influence responses to enteric challenges. Therefore, this study evaluated the effects of corn type (yellow corn, YC; orange corn, OC) and coccidiosis challenge (challenged, C+; non-challenged, C-) on broiler (Cobb 500) meat quality. Treatments were arranged in a 2 × 2 factorial RCBD, with eight replicate pens per treatment and 15 birds per pen. The pen was the experimental unit. Breast meat was evaluated for yield, pH, instrumental color, woody breast severity, texture, water-holding capacity, lipid oxidation, and composition. Data were analyzed using PROC GLM in SAS 9.4, with a house section included as a blocking factor. Corn type × challenge interactions were observed for live, chilled, and whole breast weights at 2 h, with YC/C+ showing the lowest values, whereas OC/C+ maintained weights comparable to non-challenged treatments. OC/C+ increased yellowness and had the greatest woody breast incidence, while YC/C+ had the lowest severity. Coccidiosis increased thaw loss and reduced fat content, whereas cook loss, lipid oxidation, and most compositional traits were unaffected. Overall, OC/C+ had greater yield than YC/C+ under challenge but was also associated with greater woody breast severity, indicating an association rather than a causal trade-off.