Table 9.

Nitrogen and amino acid digestibility at the finisher (days 21–35) period (%).

Amino acid	Treatment							SEM	Main effects					P-value
									Protein			Gly
	SP	20CP	20CP +Gly	18.5CP	18.5CP +Gly	17CP1	17CP +Gly2		20CP	18.5CP	17CP	–	+	ANOVA	Protein	Gly	Protein × Gly
N	82.9a	77.0b	76.7b	83.7a	87.0a	84.3a	84.3a	0.68	76.8b	85.4a	84.3a	81.7	82.7	0.001	<0.001	0.269	0.186
Lys	86.6b,c	83.4c	83.2c	88.3a,b	91.4a	90.0a,b	89.6a,b	0.58	83.3b	89.9a	89.8a	87.2	88.1	<0.001	<0.001	0.293	0.139
Met	91.3b,c	89.2c	88.4c	92.7a,b	94.8a	94.0a,b	93.8a,b	0.43	88.8b	93.8a	93.9a	92.0	92.3	<0.001	<0.001	0.506	0.088
Cys	71.6b	68.0b	69.1b	81.0a,a	83.1a	80.2a	79.7a	1.09	68.4b	82.0a	80.0a	76.3	77.3	0.001	<0.001	0.455	0.719
Thr	78.0b,c	73.1c	73.4c	82.0a,b	86.3a	83.7a	83.6a	0.87	73.3b	84.2a	83.6a	79.6	81.1	<0.001	<0.001	0.127	0.134
Val	82.1b,c	77.9c,d	76.8d	85.5a,b	88.6a	87.5a	87.2a	0.80	77.4b	87.1a	87.3a	83.7	84.2	<0.001	<0.001	0.542	0.143
Ile	84.0b,c	80.2c,d	78.7d	87.0a,b	89.9a	89.0a	88.7a	0.76	79.4b	88.4a	88.8a	85.4	85.7	<0.001	<0.001	0.697	0.144
Arg	88.7b,c	87.2c	86.3c	91.3a,b	93.0a	92.5a	92.0a	0.46	86.8b	92.1a	92.3a	90.3	90.4	<0.001	<0.001	0.904	0.122
Phe	85.7b	80.1c	78.1c	88.1a,b	90.3a	91.0a	90.5a	0.86	79.1b	89.2a	90.8a	86.4	86.3	<0.001	<0.001	0.869	0.194
His	84.1a	77.7b	77.0b	84.9a	88.1a	86.2a	85.7a	0.73	77.3b	86.5a	85.9a	82.9	83.6	0.007	<0.001	0.449	0.136
Leu	84.2a	76.7b	75.1b	84.4a	86.8a	86.2a	85.8a	0.86	75.9b	85.6a	86.0a	82.4	82.6	0.004	<0.001	0.919	0.373
Gly	79.1b,c	72.3e	74.1d,e	78.7b-d	85.7a	76.4c-e	82.0a,b	0.78	73.2c	82.2a	79.2b	75.8b	80.6a	<0.001	<0.001	<0.001	0.059
Ser	81.9a,b	75.1c	74.5c	81.0a,b	84.1a	78.6a-c	78.3b,c	0.68	74.8c	82.6a	78.5b	78.3	79.0	<0.001	<0.001	0.505	0.299
Ala	81.0a	69.8b,c	69.2c	77.6a,b	80.6a	74.5a-c	75.1a-c	0.93	69.5b	79.4a	74.8a	74.0	75.0	0.001	<0.001	0.517	0.610
Pro	85.7a	80.5b	80.3b	86.9a	89.0a	87.1a	86.5a	0.59	80.4b	87.9a	86.8a	84.8	85.2	0.001	<0.001	0.613	0.292
Asp	79.9a	72.6b	71.7b	78.1a,b	82.0a	72.4b	71.8b	0.83	72.1b	80.1a	72.1b	74.4	75.2	<0.001	<0.001	0.535	0.247
Glu	88.3a,b	84.4b,c	82.8c	89.0a	90.8a	92.1a	91.7a	0.62	83.6b	89.9a	91.9a	88.5	88.4	0.009	<0.001	0.928	0.202

^a–eDiffering superscripts indicate significant differences between means (P < 0.05).

Abbreviations: N, nitrogen; Lys, lysine; Met, methionine; Cys, cysteine; Thr, threonine; Val, valine; Arg, arginine; Phe, phenylalanine; His, histidine; Leu, leucine; Gly, glycine; Ser, serine; Ala, alanine; Pro, proline; Asp, aspartic acid; Glu, glutamic acid; SP, standard protein; 20CP, 20% crude protein treatment; 20CP+Gly, 20% crude protein treatment with glycine supplemented; 18.5CP, 18.5% crude protein treatment; 18.5CP+Gly, 18.5% crude protein treatment with glycine supplemented; 17CP, 17% crude protein treatment; 17CP+Gly, 17% crude protein treatment with glycine supplemented.

¹One replicate removed due to insufficient digesta samples for amino acid analysis.