The tongue is made up of several groups of muscles, which move in various directions. The tongue of a cat is a unique in that it contains backward facing spines (called papillae) which form a barbed surface and act as a hairbrush when the cat is grooming itself.
The tongue has multiple purposes such as to assist with grooming and removing food debris from the mouth and face, lapping up water, tasting food, sensing the temperature and texture of food and the tongue also assists with the swallowing of food.
A healthy tongue is pink in colour. Any change in your cat's tongue shape or colour can be an indicator of a problem and should be assessed by a vet.
Why do cats tongues feel like sandpaper?
This is due to the papillae on the tongue. There are four types of papillae:
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1) Filiform papillae (also known as conical papillae), which is the most common form of papillae. These point backwards, which assists with grooming and also help the cat remove flesh from the bones of their prey. They are located on the front half of the tongue. This is what causes the rasping or sandpaper sensation when your cat licks you.
2) Foliate papillae (meaning "leaf-like") these are the largest papillae found on the tongue. They are arranged in two groups, on either side of the tongue, in front of the circumvallate papillae.
3) Fungiform papillae, as the name would suggest, these papillae are mushroom shaped and are found along the sides of the tongue.
4) Circumvallate papillae (also known as vallate papillae), located at the back of the tongue. These dome-shaped papillae are arranged in a v-shaped row behind the fungiform papillae.
What can cats taste?
The cat's sense of smell is considerably more developed than ours, however, cats have relatively few taste buds, numbering 473, compared to humans who have 9,000. The taste buds are located on the flattened, fungiform and circumvallate papillae but not the filiform papillae.
The jury still seems to be out as to whether cats can taste sweet or not. But some now believe they can taste sweet, but it is a very underdeveloped taste compared to that of salt, sour and bitter.
The cat's tongue also has a sensitivity towards temperature, the preferred temperature is around 30C (86F). Many cat owners will be aware that cats do not like to eat food straight out of the refrigerator for this reason.
Cat tongue disorders:
There are a number of disorders to affect the tongue, including:
Glossitis - An inflammation of the tongue.
Ulcers - Caused by some viral infections, eosinophilic granulomas can occur on the tongue.
Foreign body - Such as string can be wrapped around the tongue, or bone fragments lodged in the tongue.
Cancer - Cats can develop cancer of the tongue.
Cat tongue sticking out:
This seems to happen quite a lot, typically after your cat has been grooming or during a nap. There will be a small portion of tongue left sticking out of the mouth. This is perfectly normal and nothing to worry about. He just forgot to put it back in ;) However, if you notice your cat's tongue sticking out followed by other symptoms or signs of distress, it is worth a check up with the vet.