Which essential fatty acid is specifically required by cats but not by dogs?

Cats have a specific dietary requirement for arachidonic acid, which is an essential fatty acid that they cannot synthesize from dietary precursors. While dogs can convert linoleic acid (an omega-6 fatty acid) into arachidonic acid, cats lack this enzymatic capability and must obtain arachidonic acid directly from their diet. This fatty acid plays crucial roles in various physiological processes, including the production of eicosanoids, which are signaling molecules important for inflammatory responses and overall health.

In contrast, dogs do not require arachidonic acid in their diet because they can produce it from linoleic acid, making it non-essential for them. Therefore, arachidonic acid is uniquely essential for cats and highlights the differences in fatty acid metabolism between these two species.