Table 2.

Summarized data from N-balance experiments (n = 6) with chicks (genotype Cobb 500) fed with a crude protein level of 21.5% in age period (5 to 15 d)

dThr1	Mean BW				Feed intake				N retention2
	0.64% Gly	0.98% Gly	Avg.	p-value	0.64% Gly	0.98% Gly	Avg.	p-value	0.64% Gly	0.98% Gly	Avg.	p-value
0.45%	188a±14	192a±17	190±15	<0.001	22.6a±0.7	23.7a±0.4	23.1± 0.8	<0.001	1,822a±35	1,863a±46	1,844± 44	<0.001
0.60%	237b±18	241b±20	239±19		31.0b±0.5	32.1b±0.8	31.5±0.9		2,291b±52	2,321b±63	2,306±58
Avg.	213±30	217±31	215±30		26.8±4.4	27.9±4.4	27.3±4.4		2,078±249	2,092±244	2,085±241
p-value	0.587			0.982*	<0.001			0.949*	0.116			0.786*

Values indicate mean±SD (n = 6).

¹True digestible threonine (AminoDat 1.1, Degussa, 1997).

²mg/BW_kg^0.67 per d.

^a,bDifferent superscripts within a row indicate significant differences (p<0.05; t-test).

^*p-value of interaction effect.