A new study published in PLOS ONE that examined bitter taste receptors in cats may provide evidence as to why felines are such finicky eaters.
Unlike my cat that seems to take after Garfield in his dietary choices, most cats are purely carnivorous. Cats are reportedly unable to taste sweets thus plant-based starches are not typically desirable. This is because part of the gene that encodes for sweet tastes is not functional.
Since bitter tastes are also often derived from toxic plants, the new study examined bitter taste receptor expression in domestic cats. They hypothesized that similar to sweet taste receptors, carnivorous animals would have fewer bitter taste receptors than herbivores. Contrary to their hypothesis, they found that cats have seven bitter taste receptors, which is actually similar to other carnivores including dogs, polar bears and ferrets. The researchers mentioned one reason carnivores may have kept these bitter receptors is to detect bitter tastes the animals may be exposed to through the ingestion of plant-eating prey. They also suggested that bitter receptors within the respiratory tract may help detect infections.
This research may also explain why it is so difficult to give my cat medicine...
Lei W, Ravoninjohary A, Li X, Margolskee RF, Reed DR, Beauchamp GK, Jiang P. Functional Analyses of Bitter Taste Receptors in Domestic Cats (Felis catus). PLOS ONE. October 2015. DOI: 10.1371/journal.pone.0139670