Table 5.

Main effects of dietary Leu, Ile, and Val concentrations on N balance of growing pigs, as-fed basis

Main effect	SID Leu:Lys, %		SID Ile:Lys, %			SID Val:Lys, %				P-values
Item	100	300	43	53	63	60	70	80	Pooled SEM	Leu	Ile	Val
Feed intake, g/d	968	962	962	966	967	965	963	967	12	0.140	0.516	0.807
N intake, g/d	24.0	23.8	23.8	23.9	24.0	23.9	23.8	24.0	0.3	0.212	0.498	0.593
N output in feces, g/d	4.01	3.93	4.02	3.92	3.97	4.06	3.90	3.95	0.26	0.425	0.684	0.361
N output in urine, g/d	3.87	4.32	4.19	4.07	4.03	4.25	4.05	3.98	0.45	0.009	0.750	0.403
ATTD of N, %	83.2	83.5	83.1	83.6	83.4	83.0	83.6	83.5	1.1	0.535	0.565	0.374
N retention, g/d	16.1	15.6	15.6	16.0	16.0	15.6	15.9	16.0	0.6	0.024	0.356	0.236
N retention, %	67.1	65.3	65.5	66.6	66.6	65.2	66.6	66.9	2.1	0.041	0.488	0.212
Biological value1, %	80.6	78.2	78.8	79.7	79.8	78.6	79.6	80.1	2.2	0.008	0.620	0.346

¹Biological value was calculated as [N retained/(N intake – N output in feces)] × 100 (Mitchell, 1924).