Table 2.

COG function classes identified in the duodenal microbiome of ducks.

COG_class	Description	CD1	HD2	P value
R	General function prediction only	11.75 ± 0.51	11.58 ± 0.34	0.534
E	Amino acid transport and metabolism	8.36 ± 0.91	7.77 ± 0.38	0.170
S	Function unknown	8.04 ± 0.64	7.72 ± 0.37	0.320
K	Transcription	7.34 ± 1.05	7.57 ± 0.42	0.621
G	Carbohydrate transport and metabolism	7.28 ± 1.52	7.78 ± 0.69	0.486
J	Translation, ribosomal structure, and biogenesis	6.60 ± 0.68	6.45 ± 0.54	0.680
M	Cell wall/membrane/envelope biogenesis	6.16 ± 0.69	6.50 ± 0.14	0.276
L	Replication, recombination, and repair	6.05 ± 0.52	6.42 ± 0.24	0.149
C	Energy production and conversion	5.46 ± 0.24	5.30 ± 0.13	0.196
T	Signal transduction mechanisms	5.27 ± 1.17	5.90 ± 0.72	0.290
P	Inorganic ion transport and metabolism	5.27 ± 0.29	4.90 ± 0.14	0.017
H	Coenzyme transport and metabolism	4.50 ± 0.37	4.25 ± 0.24	0.192
O	Posttranslational modification, protein turnover, chaperones	3.64 ± 0.50	3.56 ± 0.24	0.743
F	Nucleotide transport and metabolism	2.95 ± 0.37	2.88 ± 0.28	0.743
I	Lipid transport and metabolism	2.90 ± 0.46	2.63 ± 0.12	0.202
V	Defense mechanisms	2.10 ± 0.32	2.51 ± 0.11	0.015
U	Intracellular trafficking, secretion, and vesicular transport	2.05 ± 0.37	2.10 ± 0.08	0.754
Q	Secondary metabolites biosynthesis, transport, and catabolism	1.59 ± 0.42	1.34 ± 0.12	0.203
N	Cell motility	1.44 ± 0.50	1.52 ± 0.12	0.691
D	Cell cycle control, cell division, chromosome partitioning	1.21 ± 0.16	1.28 ± 0.05	0.335
B	Chromatin structure and dynamics	0.02 ± 0.01	0.02 ± 0.01	0.581
A	RNA processing and modification	0.01 ± 0.01	0.01 ± 0.00	0.260
Z	Cytoskeleton	0.01 ± 0.00	0.01 ± 0.00	0.812
W	Extracellular structures	0.00 ± 0.00	0.00 ± 0.00	0.343

¹CD: duodenal content samples from the control ducks.

²HD: duodenal content samples from the heat-treated ducks.