Table 1.

Proteins in select biological functional groups that were differentially expressed in the intestinal tract of day of hatch chicks that were administered Citrobacter freundii (C), Citrobacter spp. (C2), or lactic acid bacteria (L) in ovo at 18 embryonic days compared with the saline (S) control treatment. Proteins were identified by LC-MS/MS and quantified with a label-free spectral count approach. The relative protein quantitation was measured by comparing the number of MS/MS spectra identified from the same protein in each of the multiple LC/MS-MS data sets.

Biological function	Symbol ID1	Fold change relative to S4			P-value3
		C	C2	L	C	C2	L
Immune system	ALCAM	---2	---	2.88	---	---	0.07
	CAV1	---	---	−2.41	---	---	<0.01
	H2B-I	−1.99	---	---	0.02	---	---
	H4-I	2.45	---	1.94	0.02	---	0.01
	HMGB2	---	---	−2.06	---	---	0.05
	HMGB3	---	---	−4.26	---	---	<0.01
	HSP7C	−1.56	---	---	0.06	---	---
	HSP90AB1	---	−1.35	---	---	0.09	---
	HSPB1	1.89	---	1.52	0.01	---	0.09
	HSPD1	−1.46	---	---	0.06	---	---
	LAC	2.23	---	---	0.04	---	---
	PSMA7	---	---	2.21	---	---	0.01
	STAT3	---	2.85	---	---	0.08	---
Antioxidant system	CYC	−2.14	---	---	0.02	---	---
	CYB5A	−3.63	---	2.17	0.01	---	0.07
	PRDX1	3.41	1.49	2.58	<0.01	0.01	<0.01
	SOD1	---	---	2.04	---	---	0.08
Cytoskeletal assembly, cell motility, recognition	ACT5	−1.72	---	---	0.05	---	---
	ACTN1	1.45	---	---	0.06	---	---
	ACTN2	2.14	---	---	<0.01	---	---
	ACTN4	1.38	---	1.34	0.08	---	0.02
	ATP2A2	−5.74	---	---	0.03	---	---
	COL1A1	1.87	---	1.41	0.01	---	0.02
	COL6A2	---	---	−1.35	---	---	0.08
	COL6A3	---	4.42	---	---	0.08	---
	CTTN1	---	---	1.42	---	---	<0.01
	DES	−1.89	---	−1.89	0.06	---	<0.01
	DMD	−1.84	---	−1.78	0.04	---	0.02
	DPYSL2	1.79	---	---	0.08	---	---
	DSTN	−9.00	1.66	---	<0.01	0.02	---
	DYNC1LI1	---	1.41	1.61	---	0.00	0.05
	GSN	−1.88	---	---	---	0.03	---
	M7BG31	−1.92	---	−1.73	0.05	---	0.08
	MAPRE1	−1.92	−1.52	−1.73	0.05	0.50	0.08
	MARCKS	1.58	---	---	---	0.08	---
	MLEX	−1.53	---	---	---	0.01	---
	MYH9	1.59	---	---	---	0.02	---
	MYLK	−2.04	−1.82	−2.61	0.08	0.04	0.08
	MYO1A	1.45	---	---	---	---	0.06
	PDLIM7	1.79	−1.73	---	0.01	0.02	---
	PLS1	---	3.88	---	---	<0.01	---
	RDX	−1.65	---	---	0.08	---	---
	SLC9A3R1	2.81	1.87	---	0.03	0.04	---
	TAGLN	---	---	−7.80	---	---	0.06
	TUBA1A	1.86	---	---	<0.01	---	---
	TBA1	−2.69	---	---	0.03	---	---
	TBA8	1.50	---	---	0.08	---	---
	TPM1	1.86	---	---	0.01	---	---
	TBB2	−1.69	---	---	0.06	---	---
	TNS	---	2.61	−3.10	---	0.05	0.09
	TPM1	2.55	---	---	0.01	---	---
	TPT1	---	---	−2.07	---	---	0.05
	VCL	---	---	−1.53	---	---	0.04

¹Symbol ID, protein identification and function were found on the UniProtKB database in the Gallus gallus reference.

²--- = No difference fold change relative to the S control treatment, therefore values were not reported.

³P-values were derived with a Student's t-test in relation to the S control treatment. Values recorded were at P ≤ 0.10.

⁴Fold changes with P-values at ≤ 0.05 were bolded.