Researchers discover how cats use urine to identify one another

An international research team, including scientists from Iwate University in Japan, has discovered that domestic cats use specific chemical signatures in their urine to identify one another. According to a study published in ‘Current Biology’, these unique scent fingerprints are composed of 13 types of branched-chain fatty acids (BFAs).

Researchers observed that cats exhibit the ‘flehmen response’—a distinctive facial expression involving a slightly open mouth—when sniffing these scents. The study found that these BFAs act as stable, long-lasting identifiers because they are stored in reservoirs within the renal cortex. This mechanism allows a cat's chemical ID to remain consistent despite changes in diet, age, or health.

Similar compounds were also detected in other feline species, such as lions and tigers. Scientists suggest these findings could assist in monitoring rare feline species and developing methods to suppress urine odors. Additionally, understanding how these fatty acids accumulate in the kidneys may provide insights into both feline and human renal health.