Page 678 - Veterinary Immunology, 10th Edition

VetBooks.ir Odors

Another way the microbiota affect their host is by increasing the
diversity of the communication signals available to the host. Thus it

is postulated that bacteria in mammalian scent glands as well as
those in the mouth and the intestine generate odorous metabolites
such as short-chain fatty acids. Some of these odors are used for
host communication. Variations in these host chemical signals may
be a result of underlying variations in the microbiota of the scent

glands. Thus surveys of the microbiota of hyena scent glands
suggest that variations in their microbiota correlate with the
volume and fatty acid profiles of scent secretions. The bacterial

populations also vary with species, gender, pregnancy, and
reproductive state. In other mammals, odors are used for kin
identification and mate choice. Given that genes for many odor
receptors are linked to the MHC, it is not difficult to imagine how
animals recognize others by the odors generated by their

microbiota.

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