Dietary methionine requirement of Jing Brown layer hens from 9 to 17ￂ weeks of age

• Published in: Journal of animal physiology and animal nutrition 2017-10, Vol.101 (5), p.925
• Main Authors: Meng, G H, Song, D, Li, L B, Yang, C J, Qu, Z X, Gao, Y P
• Format: Article
• Language: English
• Subjects: Alkaline phosphatase; Corn; Diet; Dietary supplements; Eggs; Follicles; Hormones; Jejunum; Methionine; Poultry; Reproduction; Reproductive system; Systems development; Uric acid
• ISSN: 0931-2439; 1439-0396
• DOI: 10.1111/jpn.12525

Summary This study was conducted to evaluate the effect of dietary methionine (Met) supplementation in growth performance and reproductive performance of Jing Brown layer hens. A total of 375 9-week-old Jing Brown layer hens were allocated equally to five treatments consisting of 5 replicates with 15 hens. Hens were fed with a diet of corn and soya bean meal supplemented with 0.23%, 0.27%, 0.31%, 0.35% and 0.39% Met respectively. Different Met levels did not significantly affect average daily feed intake (ADFI), average daily gain (ADG) and feed/gain ratio (F/G) (p > 0.05), whereas flock uniformity (FU) and jejunum index were significantly different (p < 0.05), and the largest FU was observed in 0.31% Met. Dietary supplementation of Met significantly affected reproductive system development (p < 0.05), and 0.27-0.31% Met obtained optimal reproductive system development. Different Met levels significantly affected serum uric acid and alkaline phosphatase. Moreover, the relatively higher reproductive hormones in serum were observed in 0.27% Met. Analysis of quadratic curve estimation of flock uniformity, the total number of follicles, the primary follicles and the secondary follicles showed that the optimal Met levels were 0.293%, 0.286%, 0.286% and 0.288%, which could be averaged to 0.288%. These results suggested that the optimal Met requirement for Jing Brown layer hens from 9 to 17 weeks old is 0.29%.