Scientists uncover how cats identify each other by urine scent in Japan

Morioka, Japan (Kyodo) -- Domestic cats identify each other by detecting distinct smells in their urine, according to a recent study published in a scientific journal. A group of researchers, including those from Japan, examined urinary components that trigger a specific facial expression, known as the "stinky face" or flehmen grimace, in cats. Cats obtain information about other individuals through the scent of their urine, but the specifics of these identifying components were previously unknown.

The researchers discovered that unique combinations and proportions of branched-chain fatty acids, sourced from a cat's kidney reservoir, create individual odor marks. These marks remain detectable for an extended period and vary between individual cats. Similar compounds were also found in the urine of other feline relatives, such as lions, tigers, and Iriomote cats.

These findings, electronically published in Current Biology, could potentially be used to manage urine odor or monitor rare feline species. Professor Masao Miyazaki, a faculty member at Iwate University's Faculty of Agriculture, explained that studying the accumulation of fatty acids in cat kidneys may also contribute to research on related diseases in both cats and humans.