Table 4. Metabolites profiles (mg/100 g) of pork loin raised under different selenium supplementation conditions and storage period

Item	Treatment	Storage period (days)			SEM¹⁾
Item	Treatment	0	7	14	SEM¹⁾
Free amino acids
Alanine	Con²⁾	29.67	22.10	28.83	2.752
	Se15	24.89^ab	22.15^b	31.60^a	2.291
	Se45	28.67	26.81	33.32	2.033
	SEM	3.125	1.922	1.870
Asparagine	Con	3.54^b	3.77^b	6.67^a	0.770
	Se15	2.93^b	4.11^ab	4.95^a	0.451
	Se45	3.21^b	4.64^ab	6.08^a	0.606
	SEM	0.506	0.497	0.813
Creatine	Con	391.88^b	431.87^b	509.16^a	16.008
	Se15	406.25^c	453.50^b	488.20^a	9.882
	Se45	410.58	476.93	504.61	30.326
	SEM	10.728	30.223	15.654
Glutamate	Con	7.08^b	8.34^b	12.49^Ba	1.179
	Se15	8.87^b	10.99^ab	14.211^ABa	1.284
	Se45	9.05^b	11.28^b	16.74^Aa	0.996
	SEM	1.161	1.194	1.121
Glutamine	Con	27.97^a	16.53^b	18.89^b	2.882
	Se15	25.37	17.02	18.51	3.409
	Se45	26.81	22.90	19.65	2.703
	SEM	4.629	2.143	1.105
Glycine	Con	26.71	34.43	41.64	7.313
	Se15	28.90^b	36.20^ab	43.24^a	3.604
	Se45	27.88	36.75	36.57	4.295
	SEM	4.004	5.113	6.537
Isoleucine	Con	2.47^b	4.25^b	7.40^a	0.868
	Se15	2.96^c	5.80^b	8.93^a	0.430
	Se45	3.48^b	5.24^b	8.43^a	0.786
	SEM	0.269	0.728	0.977
Leucine	Con	2.80^b	5.28^b	9.22^a	1.197
	Se15	4.18^c	7.12^b	11.27^a	0.667
	Se45	4.12^b	6.65^b	10.95^a	0.975
	SEM	0.568	0.983	1.241
Methionine	Con	5.59^b	6.82^b	11.39^a	1.250
	Se15	5.12^c	8.79^b	11.96^a	0.636
	Se45	5.97^b	8.97^b	12.71^a	1.107
	SEM	0.345	1.18⁶	1.290
Phenylalanine	Con	2.68^c	5.13^b	7.96^a	0.743
	Se15	3.35^c	6.34^b	9.54^a	0.304
	Se45	3.83^b	5.92^b	9.25^a	0.722
	SEM	0.192	0.653	0.838
Taurine	Con	38.23	35.77	40.20	4.510
	Se15	36.53	40.09	43.24	3.619
	Se45	46.18	42.41	38.74	2.928
	SEM	3.399	4.239	3.534
Threonine	Con	6.30^c	9.82^b	12.72^a	0.920
	Se15	7.28	13.99	13.14	1.950
	Se45	7.71^b	11.35^a	13.83^a	1.073
	SEM	0.429	2.217	0.839
Tyrosine	Con	3.69^Bb	8.54^b	14.82^a	1.632
	Se15	4.45^Bc	10.18^b	16.50^a	0.708
	Se45	5.60^A	10.19	16.78	1.408
	SEM	0.307	1.288	1.842
Valine	Con	4.16^b	6.10^b	9.68^a	1.124
	Se15	4.78^c	7.94^b	11.87^a	0.627
	Se45	5.70^b	7.58^b	11.60^a	0.992
	SEM	0.439	0.941	1.250
β-alanine	Con	7.49	7.33	8.40^AB	0.591
	Se15	7.72	7.96	7.99^B	0.381
	Se45	7.84	9.05	9.55^A	0.498
	SEM	0.393	0.641	0.420
Nucleotide-related products
Hypoxanthine	Con	11.43	9.47	12.92	1.168
	Se15	11.74^ab	10.15^b	13.40^a	0.709
	Se45	12.24	11.69	13.47	1.051
	SEM	1.373	0.745	0.731
IMP	Con	79.80	92.02	76.74	5.137
	Se15	89.49	90.69	73.91	5.777
	Se45	90.51	100.20	82.46	7.372
	SEM	7.590	7.072	2.549
Inosine	Con	37.95^Bb	54.53^b	75.34^a	6.024
	Se15	37.73^Bc	57.22^b	77.24^a	2.165
	Se45	42.24^Ac	60.48^b	74.93^a	4.201
	SEM	0.820	4.769	5.934
UMP	Con	2.94	3.68	2.95	0.212
	Se15	3.52	3.65	3.54	0.173
	Se45	3.20	3.48	3.16	0.232
	SEM	0.215	0.217	0.188
Organic acids
Acetate	Con	3.41^b	4.73^b	6.55^a	0.434
	Se15	3.37^c	5.33^b	7.16^a	0.269
	Se45	3.99	5.33	5.95	0.529
	SEM	0.223	0.467	0.522
Lactate	Con	266.39^b	345.02^a	389.90^a	18.649
	Se15	284.39^b	360.10^a	384.63^a	13.010
	Se45	277.13^b	362.30^a	371.84^a	24.988
	SEM	16.370	24.980	15.794
Methylmalonate	Con	5.59^b	7.15^b	8.96^a	0.529
	Se15	6.15^b	8.04^a	8.79^a	0.297
	Se45	5.68^b	7.82^a	8.60^a	0.590
	SEM	0.302	0.560	0.557
Others
Betaine	Con	34.96^B	30.79	30.13	2.225
	Se15	34.86^B	35.28	28.78	4.596
	Se45	46.01^A	44.94	38.50	3.970
	SEM	2.740	3.920	4.355
Carnosine	Con	224.98^b	313.86^a	357.50^a	15.515
	Se15	284.85	323.75	347.96	27.245
	Se45	221.90^b	315.65^a	337.96^a	28.333
	SEM	28.347	27.062	15.810
Ethanol	Con	0.88	1.78	2.28	0.391
	Se15	1.04^b	2.47^a	2.40^a	0.141
	Se45	1.04^b	2.19^a	2.25^a	0.285
	SEM	0.107	0.253	0.423
Glucose	Con	42.92	72.18	81.68	19.945
	Se15	46.56^b	74.86^ab	87.63^a	9.465
	Se45	67.56	89.19	77.10	25.165
	SEM	17.404	18.664	21.666
Glycerol	Con	9.06	9.29	10.76	1.339
	Se15	9.65	9.24	12.96	1.112
	Se45	11.32	10.64	11.31	0.627
	SEM	0.829	0.892	1.393
Methanol	Con	0.74^a	0.30^b	0.33^b	0.105
	Se15	0.61	0.38	0.35	0.082
	Se45	0.75	0.49	0.41	0.100
	SEM	0.136	0.091	0.033
N,N-Dimethylglycine	Con	1.93^b	2.27^b	2.81^a	0.158
	Se15	1.90^c	2.45^b	2.71^a	0.055
	Se45	2.01^b	2.58^ab	2.83^a	0.190
	SEM	0.058	0.189	0.158
Niacinamide	Con	4.55^b	6.70^a	7.69^a	0.471
	Se15	5.05^c	6.99^b	7.86^a	0.244
	Se45	5.16^b	6.91^a	7.60^a	0.537
	SEM	0.351	0.564	0.358
O-Acetylcarnitine	Con	7.56^a	2.60^b	3.46^b	0.783
	Se15	7.51	3.64	3.96	1.300
	Se45	7.66^a	4.56^b	4.14^b	0.764
	SEM	1.541	0.658	0.280

n = 15.
Con, fed basal diet; Se15, pork loin from feeding organic Se 0.15 ppm + inorganic Se 0.10 ppm; Se45, pork loin from feeding organic Se 0.45 ppm + inorganic Se 0.10 ppm.
Different letters within the same column indicate significant differences (p < 0.05).
Different letters within the same row differ significantly (p < 0.05).