My cat, unfortunately, got off on the wrong foot and as you can see usually drinks his lunch.
Posted on 07/25/2005 11:22:58 AM PDT by LibWhacker
As cat owners know, their feline friend would much rather chase and eat a live mouse than snack on the chocolate equivalent, and now researchers have discovered the reason – cats are simply unable to taste sweet things.
An examination of feline genetics has shown a significant defect in one of the genes that codes for part of the sweet taste receptor. This “huge deletion” of 247 base pairs in the gene that codes for the T1R2 protein – one of two proteins that make up the sweet taste receptor in mammals – has left cats unable to detect sweet-tasting compounds like sugars and carbohydrates.
It explains the indifference that domestic cats, lions, tigers, leopards and jaguars have been reported to show towards sweet foods. And it may also explain why they have evolved into such accomplished hunters, says Joseph Brand, professor of biophysics at Monell Chemical Senses Center in Philadelphia, US, and one of the study’s authors. “But it could be the other way around,” he suggests. “What came first: carnivorous behaviour or the loss of the T1R2 protein? With regard to the gene, is this a case of use it or lose it?” he asks.
Gene hunter
Looking down the family tree may provide clues. Brand has also found the mutant gene in cheetahs and tigers, and in their more distant relation, the hyena. So, although it seems clear that an ancestor of the big cats and the hyena must have possessed the faulty gene, Brand does not know on which branch of the evolutionary tree it first occurred. “Almost certainly the ancestral mammal would have been a successful hunter, or it would not have survived losing its sweet taste bud.
“And losing it may well have given wild cats a certain food niche that other animals can’t get into – most other animals need to hunt in packs, but big cats have developed the strength to hunt alone,” Brand told New Scientist. “But it’s a hard way of getting nutrition: they must hunt it, eat it, remove the nitrogen and only then can they use it.”
Carnivores’ diets are much less efficient than the omnivorous diets of many other large mammals, although parts of a hunted animal do contain carbohydrate - especially the liver - so it is possible that cats may be able to metabolise these energy stores.
Violent reaction
Coupled with the loss of sweet taste receptors in cats is a deficiency of sucrase in cats – the enzyme that digests sucrose. A consequence of this can be seen in cats that accidentally drink water containing sucrose. This makes them violently ill, but, since they cannot taste the sugar, they are unable to develop an aversion and so often drink more of the liquid, with the same results.
The mouth is not the only place where taste buds occur, Brand says. They also exist in the digestive tract and pancreas, where the sweet tasting receptors are also defective. Since the role of taste buds in places other than the mouth is unknown, the consequence of defective ones is also unclear, he says.
But, cats may be compensating for their lack of a sweet tooth. “Felines have very complex amino acid taste receptors. We have no idea what meats taste like to a cat: they may have sophisticated receptors to other taste stimuli that we just don’t know about,” Brand says.
"Our results account for the common observation that the cat lives in a different sensory world to the cat owner," comments team member Véronique Legrand-Defretin, director of the global feeding behaviour research programme at the Waltham Centre for Pet Nutrition in Leicestershire, UK.
With all the table scraps he likes, why do I bother to buy cat food?
You need to take photos of that and post here on FR!
In related research, scientists have succeeded in modifying the human genome to erase the sweet taste sense from people. While this is a promising treatment for obesity, side effects of this treatment include a person's new, strong urge to lick themselves clean, and a craving to climb into empty boxes and paper bags...
I had a cat that really liked cooked white rice.
I knew dogs liked "people" food but didn't know that about cats. My Corgi just loves raw carrots. I used to give him grapes until I found out it was bad for dogs.
My dog eats grapes all the time...what's so bad about them?
guess they need to make meat flavored antifreeze then...
My kitty comes running whenever a can is opened... but declines when the stuff inside is only diced pineapple.
My diabetic putty loves ice cream and yogart???????
read later bump
One of them will also eat potato chips.
I've got some photos of that somewhere on my hard-drive. I'll try to dig 'em up.
Does this mean covering yourself in honey is the best defense against a mountain lion?
My cat, unfortunately, got off on the wrong foot and as you can see usually drinks his lunch.
My diabetic cat likes cornbread. With butter.
Perhaps thirst and proximity when thirst hits? My cat used to drink out of a bowl of water next to the garage kept for cleaning shoes when his dish with fresh, clean water was just inside the garage. He would've had to walk all of a few feet though, and that might've conflicted with his economy-of-movement philosophy.
And yet they can't figure out how cats make the purr noise.
"purr noise"...the most delightful sound in the world.
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