Kshiti Vyas
If cats were restaurant critics, they would probably leave a one-star review with a comment saying, “I wouldn’t even feed this to my arch-nemesis, the vacuum cleaner”.
Cats are known for their picky habits, especially when it comes to food. Cat owners might know what a struggle it is to feed your feline friend without losing a finger. It has been observed that these feline friends have very “fishy” choices. In several studies conducted, it was observed that cats choose meat over any other food, especially fish. Fish has several proteins, taurines and omega-3 fatty acids, beneficial for cat’s health. The Cat-Fish affair is considered to be ancestral and not a new thing but looking at evolution, felines have evolved from the Middle-Eastern ecosystem, whereas their “fishy” friends have evolved totally in marine ecosystem. So how did this feline-fish affair develop?
In a recent study published in Chemical Senses showed that scientists were finally able to figure out why cats love fish, especially tuna. This study was conducted by providing several amino acids in combination to some nucleotides to check for the attraction of Umami taste in cats. Umami is the savory taste of meat, produced mainly due to presence of certain compounds like glutamate, inosinate and guanylate. In humans and many other animals, specific group of genes called Tas1r1 and Tas1r3 are responsible for recognizing the umami taste and so when activated, these genes act as receptor for the umami taste. Studies have confirmed the expression of both these genes in cats.
Image Source: Google Images
The study reveals that purine nucleotides (AMP, GMP, IMP and XMP) are agonists of the umami receptor when tested alone, where an agonist is any substance that elicits biological response when bound to a receptor.
On the other hand, the pyrimidine nucleotides (CMP and UMP) did not elicit any such response. When tested with L-Alanine the response of purine nucleotides enhanced but that of pyrimidine nucleotides remained the same.
Moreover, cats require 10 essential amino acids, including L-Histidine, L-Leucine, L-Methionine, L-Phenylalanine and L-Tryptophan. Fascinatingly, these amino acids are also enhancers for receptors for umami taste in cats. When added to the food, L-Histidine was specifically preferred over all other amino acids by cats which suggests that L-Histidine is possibly a highly palatable amino acid for cats, mainly because of its essential nutritional value and umami taste enhancement.
Now the scientists decided to combine both, nucleotides as well as amino acids and check the effect. They found that cats showed a significant preference for mixture of L-amino acids with nucleotides compared to either of them alone. This shows that there is a significant synergy between amino acids and nucleotides in enhancing the umami taste in cats.
Combining all these data, the text also suggests that high-IMP content and free L-Histidine in tuna might be a key factor contributing to its high palatability in cats.
This adaption to meat detection may help promote protein intake in cats. These findings can be very helpful to design medicines for cats as well as to fortify their food. And this may also save your finger while feeding to your cat.
Image Source: Google images (Originally published in The Times Of India)
Reference:
1. Scott J McGrane, Matthew Gibbs, Carlos Hernangomez de Alvaro, Nicola Dunlop, Marcel Winnig, Boris Klebansky, Daniel Waller, Umami taste perception and preferences of the domestic cat (Felis catus), an obligate carnivore, Chemical Senses, Volume 48, 2023, bjad026, https://doi.org/10.1093/chemse/bjad026
2. https://pubmed.ncbi.nlm.nih.gov/33580387/
3. Images: Google Images