Effects of ${\rm \small L}$-methionine on growth performance, carcass quality, feather traits, and small intestinal morphology of Pekin ducks compared with conventional ${\rm \small {DL}}$-methionine

• Published in: Poultry science 2019-12, Vol.98 (12), p.6866-6872
• Main Authors: Zhang, Y N, Xu, R S, Min, L, Ruan, D, Kim, H Y, Hong, Y G, Chen, W, Wang, S, Xia, W G, Luo, X, Xie, C Y, Shang, X G, Zheng, C T
• Format: Article
• Language: English
• Subjects: Animal Feed - analysis; Animals; Diet - veterinary; Dietary Supplements - analysis; Dose-Response Relationship, Drug; Ducks - growth & development; Ducks - physiology; Feathers - physiology; Intestine, Small - anatomy & histology; Male; Meat - analysis; Methionine - administration & dosage; Methionine - classification; Methionine - metabolism; Random Allocation
• ISSN: 0032-5791; 1525-3171
• DOI: 10.3382/ps/pez438

Abstract The research studied the effects of l-methionine (l-Met) on growth performance, carcass quality, feather traits, and small intestinal morphology of Pekin ducks compared with conventional dl-methionine (dl-Met). A total of 1080, 1-day-old male Pekin ducks were randomly allotted to 9 groups with 6 replicate pens of 20 birds each. During the starter phase (1 to 14 d), ducks were fed a basal diet (Met, 0.30%) or that supplemented with dl-Met or l-Met at 0.05, 0.10, 0.15, or 0.20% of feed. During the grower phase (15 to 35 d), ducks were fed a basal diet (Met, 0.24%) or that supplemented with dl-Met or l-Met at 0.04, 0.08, 0.12, or 0.16% of feed. Compared with ducks fed the basal diet, supplementation with either dl-Met or l-Met increased the body weight (BW) of ducks at days 14 and 35, increased average daily gain (ADG) and average daily feed intake (ADFI), decreased F:G at the starter phase, and increased ADG over the whole 35-d period (P < 0.05). The efficacy of l-Met compared to dl-Met was 140.1% for 14-d BW, 137.6% for ADG and 121.0% for F:G for days 1 to 14. Ducks fed diets supplemented with l-Met had greater proportion of leg muscle, higher than in ducks provided with dl-Met (P < 0.05). The breast muscle proportion was enhanced with dl-Met rather than l-Met supplementation (P < 0.01). The back feathers score and fourth primary wing feather length were increased with dl-Met or l-Met supplementation (P < 0.01), and there was increased efficacy of l-Met relative to dl-Met for back feathers score (153.1%). Dietary dl-Met or l-Met supplementation increased villus height of ileal mucosa of ducks at days 14 and 35 (P < 0.01). Overall, dietary l-Met or dl-Met supplementation affected the growth performance of ducks during the starter phase, and improved the feather traits and small intestinal morphology. The efficacy of l-Met to dl-Met ranged from 120 to 140% for growth performance of young ducks (1 to 14 d) and was 153% for the feather traits of ducks (35 d).