Table 5.

Influence of broiler age on the retention (% of intake) of dry matter (DM) and nitrogen (N), apparent metabolizable energy (AME; kcal/kg DM basis) and nitrogen-corrected AME (AMEn; kcal/kg DM basis) of barley grain¹.

Age (wk)	DM retention	N retention	AME	AMEn
1	77.9	61.5	3,391	3,286
2	69.3	40.9	3,057	2,988
3	72.9	46.2	3,195	3,117
4	71.6	43.8	3,164	3,090
5	71.0	42.5	3,105	3,035
6	71.6	41.3	3,150	3,081
SEM2	0.46	1.31	19	17
Orthogonal polynomial contrast, P ≤
Linear	0.001	0.001	0.001	0.001
Quadratic	0.001	0.001	0.001	0.001

¹Each value represents the mean of six replicates. The number of birds per replicate cage were 10 (wk 1) and 8 (wk 2–6).

²Pooled standard error of mean.