Uropygial gland size and composition varies according to experimentally modified microbiome in Great tits

Table 1 Composition of Great tit uropygial gland secretions

	Compound	Formula	PC1	PC2	PC3
A	Pentadecyl octadecanoate	C33H66O2	0.39	−0.11	0.54
B	Hexadecyl 9-octadecenoate	C34H66O2	−0.88	−0.17	0.24
C	Hexadecyl octadecanoate	C34H68O2	−0.29	−0.72	0.16
D	Nonadecyl hexadecanoate	C35H70O2	0.55	−0.14	0.56
E	Unidentified	C35H70O2	0.78	−0.2	0.06
F	Unidentified	C35H70O2	0.58	−0.51	−0.09
G	Heptadecyl 9-octadecenoate	C35H70O2	−0.63	0.45	0.31
H	Heptadecyl octadecanoate	C35H70O2	0.91	0.17	0.27
I	Octadecyl 9-octadecenoate	C36H70O2	−0.58	−0.41	−0.48
J	Octadecyl 9-octadecenoate	C36H70O2	−0.85	0.07	0.24
K	Octadecyl octadecanoate	C36H72O2	−0.04	0.42	−0.81
L	Unidentified	C37H74O2	0.87	0.2	0.16
M	Unidentified	C37H74O2	0.85	0.07	−0.28
N	Unidentified	C37H74O2	−0.7	0.49	0.23
O	Unidentified	C37H74O2	0.8	0.03	−0.22
P	Nonadecyl 9-octadecenoate	C37H72O2	−0.34	−0.79	−0.1

Factor loadings of the three first principal components summarizing the variance in the chemical composition of uropygial gland secretions in breeding Great tits are shown. The first component represents 45.1% of the original variance, the second 14.9% and the third 12.8% (total 72.8%). Each letter indicates a different compound in the GC-MS profiles. Variables included in each principal component are presented in bold.

ISSN: 2730-7182