Table 2. Identification of significantly different small molecular metabolites in breast meat and leg meat of YBC and PC

Source	No.	Mode	Compound name	RT/min	VIP	p-value
Breast meat	78	ESI+	Creatine	0.95	7.55	0.00
	18	ESI+	Betaine	0.91	2.88	0.02
	30	ESI+	Anserine	0.83	2.66	0.05
	66	ESI+	Inosine	1.19	2.39	0.00
	29	ESI+	L-Isoleucyl-L-proline	2.82	2.11	0.00
	17	ESI+	Creatinine	1.18	2.00	0.01
	42	ESI+	L-Palmitoylcarnitine	8.70	1.14	0.01
	48	ESI+	Tetradecanoylcarnitine	7.87	1.13	0.00
	47	ESI+	Tetracosahexaenoic acid	7.17	1.02	0.00
	12	ESI-	Anserine	0.81	6.76	0.01
	24	ESI-	Tauroursodeoxycholic acid	5.40	3.14	0.00
	66	ESI-	Sedoheptulose	0.88	2.06	0.00
Leg meat	93	ESI+	Hypoxanthine	0.93	4.04	0.00
	64	ESI+	L-Acetylcarnitine	0.91	3.84	0.00
	37	ESI+	Linoleyl carnitine	8.35	3.79	0.00
	104	ESI+	Hydrouracil	0.95	3.47	0.00
	42	ESI+	L-Palmitoylcarnitine	8.70	2.47	0.00
	66	ESI+	Inosine	1.19	1.74	0.00
	85	ESI+	Acetylcholine	0.91	1.57	0.01
	24	ESI+	β-Alanine	0.91	1.36	0.00
	25	ESI+	Glutathione	1.19	1.17	0.00
	15	ESI+	N-Acetyl-L-histidine	0.81	1.17	0.01
	20	ESI+	L-Serine	0.93	1.06	0.00
	96	ESI+	Pantothenic acid	1.91	1.03	0.01
	3	ESI+	DL-2-Aminooctanoic acid	0.91	1.00	0.00
	12	ESI-	Anserine	0.81	6.95	0.00
	65	ESI-	Pantothenic acid	2.06	2.91	0.00
	24	ESI-	Tauroursodeoxycholic acid	5.40	1.19	0.00

YBC, Yanjin blackbone chickens; PC, Piao chickens; ESI, electrospray ionization; RT, retention time; VIP, variable importance in the projection.