Table 6.

Nitrogen utilization of gilts fed different diets during gestation¹,²

	NP		LP			P-value
	−DF	+DF	−DF	+DF	SEM	CP	DF	CP × DF
Days 35 to 38
N intake, g/d	44.10	44.10	36.56	36.56	—	—	—	—
N in feces, g/d	5.93	6.83	6.27	5.68	0.84	0.523	0.810	0.246
N in urine, g/d	19.68	18.15	15.26	12.57	0.98	<0.001	0.015	0.314
N retention, g/d	18.49	19.11	15.03	18.31	1.24	0.029	0.044	0.161
N digestibility, %	86.54	84.51	82.85	84.47	2.29	0.254	0.899	0.266
N utilization (% of absorbed)	48.29	51.27	49.78	59.20	2.66	0.011	0.049	0.115
N net utilization (% of intake)	41.93	43.35	41.11	50.07	2.82	0.135	0.028	0.101
Days 65 to 68
N intake, g/d	44.10	44.10	36.56	36.56	—	—	—	—
N in feces, g/d	4.90	6.60	4.90	5.56	0.63	0.273	0.019	0.273
N in urine, g/d	21.86	19.12	17.08	12.23	1.94	0.001	0.026	0.512
N retention, g/d	17.34	18.38	14.58	18.77	2.24	0.477	0.126	0.349
N digestibility, %	88.89	85.03	86.60	84.79	1.43	0.281	0.022	0.382
N utilization (% of absorbed)	44.25	49.08	46.01	60.23	6.56	0.172	0.049	0.315
N net utilization (% of intake)	39.32	41.68	39.88	51.33	6.13	0.233	0.099	0.286
Days 95 to 98
N intake, g/d	54.96	54.96	45.58	45.14	—	—	—	—
N in feces, g/d	7.88	8.61	5.65	6.79	0.77	0.001	0.094	0.705
N in urine, g/d	18.37	16.60	15.06	10.89	1.94	0.002	0.029	0.356
N retention, g/d	28.71	29.75	24.87	27.46	1.70	0.018	0.147	0.528
N digestibility, %	85.66	84.33	87.60	84.96	1.40	0.242	0.077	0.548
N utilization (% of absorbed)	61.09	64.17	62.22	71.95	4.91	0.149	0.041	0.280
N net utilization (% of intake)	52.23	54.12	54.57	60.83	3.77	0.076	0.087	0.323

¹NP, normal CP; LP, low CP; DF, dietary fiber. DF mixture consisted of pectin, inulin, and cellulose at the ratio of 1:10:34.

² N = 6 to 9 per group.