Table 3.

Effect of crude protein level and protease enzyme supplementation on serum biochemical profile in broiler chickens at 35 days of age¹⁾

Item	Albumin (g/L)	Triglycerides (mmol/L)	Total protein (g/L)	Uric acid (μmol/L)
Diets2)
NP	11.88	0.54	30.11	248
LP1	11.33	0.74	26.83	219
LP2	10.93	0.76	26.59	249
LP3	9.73	0.86	23.78	150
SEM	0.21	0.04	0.54	11.62
Contrast, p-values
Linear	<0.001	0.011	<0.001	0.167
Quadratic	0.314	0.531	0.777	0.146
Protease
With	10.97	0.77	26.69	242a
Without	10.96	0.68	26.96	201b
SEM	0.18	0.04	0.43	9.75
Probabilities
CP	<0.001	0.017	<0.001	<0.001
Protease	0.992	0.141	0.749	0.009
CP×protease	0.048	<0.001	0.320	<0.001

SEM, standard error of mean; CP, crude protein.

¹⁾Data represent mean values of 8 birds.

²⁾NP, normal protein (starter CP21/finisher CP19); LP1, low protein diet 1 (starter CP19.7/finisher CP17.9); LP2, low protein diet 2 (starter CP18.5/finisher CP16.7); LP3, low protein diet 3 (starter CP17.2/finisher CP15.6).

^a,bMeans within a column-subgroup without common superscripts differ at p<0.05.