Research overview: felinine and sulfur compounds as feline scent signals

Cat urine contains felinine, an amino-acid-derived compound that breaks down into volatile sulfur-containing molecules responsible for the strong odor of cat marks. This overview surveys the role of felinine and its breakdown products as chemical signals used in feline communication, particularly in territorial marking. Males typically produce more felinine than females, and its degradation over time may encode information about how recently a mark was made. The survey relates felinine to the broader chemistry of scent marking and to detection by the olfactory and vomeronasal systems. It connects to the enzyme cauxin, which influences felinine output in urine. Understanding felinine links a specific biochemical pathway to the pungent signals cats leave and read. It illustrates how feline chemical communication rests on identifiable molecules whose production, excretion, and decay carry meaningful messages between cats about identity, sex, and territory.