Researchers have identified 13 branched-chain fatty acids in cat urine whose relative proportions differ among individuals yet remain comparatively stable within the same cat.
Behavioural experiments showed that cats can discriminate these donor-specific chemical profiles, while the compounds persist longer than many volatile urinary odorants. The same fatty-acid-related compounds accumulate in kidney lipid droplets, suggesting that an internal reservoir may help maintain a stable chemical identity signal that remains informative after a scent mark has been deposited.
https://phys.org/news/2026-08-year-mystery-cat-kidney-linked.html
