Table 2 Effects of dietary methionine level on growth performance of Pekin ducks from 15 to 42 days of age

0.28

86.7±2.6^b

186.2±7.9

2.15±0.06^a

0.52±0.02^e

5.95±0.16^e

0.35

89.1±3.6^a,b

176.7±10.2

1.98±0.06^b

0.62±0.04^d

6.97±0.20^d

0.43

93.4±2.6^a

179.1±8.2

1.92±0.04^c

0.76±0.03^c

8.19±0.16^c

0.50

90.8±3.0^a,b

175.5±7.2

1.94±0.04^b,c

0.88±0.04^b

9.70±0.19^b

0.58

91.8±4.6^a

177.0±9.6

1.93±0.04^b,c

1.02±0.06^a

11.12±0.25^a

 Met

0.024

0.259

<0.001

<0.001

<0.001

 Met linear response

0.014

<0.001

<0.001

<0.001

 Met quadratic response

0.077

<0.001

0.489

0.001