Table 6. Effects of supplementation of ARG sources and PHE levels on plasma parameters in cold-stressed broilers fed a CM-based diet at 38 d

Item1)	ALT (U/L)	AST (U/L)	LDH (U/L)	CK (U/L)	TAC (mmol/mL)	MDA (mmol/mL)	BUN (mg/dL)	UA (mg/dL)	TP (g/dL)	Albumin (g/dL)	Creatinine (µmol/L)	Glucose (mg/dL)
Factorial analysis
ARG sources
ARG	8.05	249.73b	1,159.93b	1596.43	1.57	1.63	1.31a	3.83b	3.83	1.57	3.53b	240.50
GAA	8.17	267.20a	1,180.00a	1561.33	1.51	1.71	1.10b	4.34a	3.67	1.54	3.80a	241.30
SEM	0.214	4.83	5.68	44.40	0.041	0.038	0.028	0.111	0.071	0.038	0.085	2.91
PHE levels
0 g/kg	7.99	254.70	1,170.90	1,609.20	1.52	1.67	1.19	4.02	3.79	1.61	3.62	238.70
1.5 g/kg	8.22	262.23	1,169.03	1,548.57	1.56	1.67	1.21	4.14	3.71	1.50	3.71	241.30
SEM	0.214	4.83	5.68	44.40	0.041	0.038	0.028	0.111	0.071	0.038	0.085	2.91
ARG sources × PHE levels
ARG × 0 g/kg	7.86	248.40	1,157.07	1,620.00	1.55	1.64	1.31	3.75	3.85	1.63	3.44	243.27ab
ARG × 1.5 g/kg	8.25	251.07	1,162.80	1,572.87	1.58	1.63	1.32	3.91	3.81	1.51	3.63	237.73ab
GAA × 0 g/kg	8.13	261.00	1,184.73	1,598.40	1.49	1.70	1.08	4.30	3.73	1.58	3.80	234.13b
GAA × 1.5 g/kg	8.20	273.40	1,175.27	1,524.27	1.53	1.71	1.11	4.38	3.61	1.49	3.79	248.47a
SEM	0.303	6.83	8.03	62.79	0.059	0.053	0.040	0.156	0.100	0.054	0.121	4.11
p-value
ARG sources	0.714	0.013	0.015	0.578	0.369	0.165	<.0001	0.002	0.123	0.538	0.033	0.846
PHE levels	0.454	0.275	0.817	0.338	0.500	0.976	0.609	0.438	0.409	0.053	0.458	0.289
ARG sources × PHE levels	0.603	0.479	0.348	0.830	0.950	0.902	0.808	0.799	0.667	0.712	0.426	0.019
Orthogonal analysis
NC2)	8.41	292.80	1,200.20	1,653.80	1.21	1.94	1.14	4.87	3.94	1.67	3.25	245.60
EG3)	8.11	258.47	1,169.97	1,578.89	1.54	1.67	1.20	4.08	3.75	1.55	3.67	240.90
GAA4)	8.165	267.2	1,180	1,561.34	1.51	1.71	1.10	4.34	3.67	1.54	3.80	241.3
p-value Ӏ5)	0.347	< .0001	0.001	0.268	< .0001	< .0001	0.193	< .0001	0.100	0.075	0.002	0.314
p-value Ⅱ6)	0.483	0.004	0.042	0.213	0.0001	0.0003	0.373	0.008	0.040	0.629	0.0003	0.400

Means in the same column with different superscripts differ significantly (p < 0.05).
NC: negative control group (birds fed CM-based diets without supplements), n = 6 replicates; for each replicate, n = 15 birds.
EG: experimental groups (other four treatments fed diets with supplements), n = 24 replicates; for each replicate, n = 15 birds.
GAA: GAA supplemented groups, n = 12 replicates; for each replicate, n = 15 birds.
Ӏ: orthogonal contrast of NC vs. EG
Ⅱ: orthogonal contrast of NC vs. GAA.
ARG, arginine; PHE, phenylalanine; BW, body weight; CM, canola meal; ALT, alanine aminotransferase; AST, aspartate aminotransferase; LDH, lactate Lactate dehydrogenase; CK, creatine kinase; TAC, total antioxidant capacity; MDA, malondialdehyde; BUN, blood urea nitrogen; UA, uric acid; TP, total protein; GAA, guanidinoactic acid.