Table 4.

Effects of low-protein diet on nitrogen balance in growing goat kids.

Variable	Crude Protein Level			SEM	p-Value 1
	14.8%	13.4%	12.0%		T	L	Q
Nitrogen intake, g/d	15.6 a	14.3 b	12.9 c	0.33	<0.001	<0.001	0.980
Fecal Nitrogen Excretion
g/d	5.07 a	4.82 a,b	4.63 b	0.101	0.0105	0.0278	0.753
% of nitrogen intake	32.5 b	33.7 a,b	35.9 a	0.85	<0.001	<0.001	0.893
Urinary Nitrogen Excretion
g/d	6.74 a	5.81 b	4.87 c	0.169	<0.001	<0.001	0.458
% of nitrogen intake	43.2 a	40.6 b	37.8 c	0.92	<0.001	<0.001	0.279
Total Nitrogen Excretion
g/d	11.8 a	10.6 b	9.51 c	0.258	<0.001	<0.001	<0.001
% of nitrogen intake	75.7 a	74.3 a,b	73.7 b	1.81	<0.001	<0.001	0.586
Nitrogen Retention
g/d	3.79 a	3.68 a	3.39 b	0.104	0.0214	0.0451	0.879
% of nitrogen intake	24.3 b	25.7 a	26.3 a	0.42	<0.001	<0.001	0.648

Means within a row with different letters differ significantly (p < 0.05). ¹ T: Treatment; L: Linear; Q: Quadratic.