According to Denise LeBeau, a writer for Catster, the average adult cat weighs around ten pounds.
Depending on the breed, however, a healthy adult cat can weigh anywhere between five and twenty-plus pounds. Some cats, however, are unusually small, and there are a variety of reasons for that.
The growth rate in cats
Newborn kittens are tiny and weigh only a few ounces. During the first six months, kittens grow rapidly and gain about a pound a month.
Their growth rate generally tapers off, and most cats are finished growing by the time they are a year old.
Jumbo-sized breeds like the Maine Coon, however, can keep growing until they are five years old. A large male of this breed can stretch four feet long from nose to tail and weigh over 20 pounds.
Small cat breeds
There are some benign reasons for a cat’s small size, and one of them is breed. Just as Maine Coons are known for being huge, some breeds are known for being small.
The Cat Breeds Encyclopedia defines a small breed as one in which the adults typically weigh less than ten pounds.
Topping the list of small breeds is the Singapura, which is often described as the smallest cat breed in the world. Some adult females can weigh as little as four pounds.
The following video, which was made by Animal Planet, describes the look and temperament of the Singapura.
Other pint-sized felines include the following:
- American Curl
- Cornish Rex
- Devon Rex
A staff writer for Cat Breed Selector described another small breed called the Toybob or ToyBobtail, which is said to get no bigger than a four-month-old kitten. Many Toybobs are pointed like Siamese cats.
Does sex affect size?
Yes. Male cats tend to be bigger than their sisters. Mary Nielsen, who writes for Feline Living, says that males will generally be larger than females of the same breed.
That last phrase is key; as Nielsen notes, “a female Maine Coon will be bigger than a male Siamese.”
Mary Nielsen also writes for All About Cats, and she states that, regardless of sex, cats that have been spayed or neutered before they reach puberty tend to grow larger than intact cats or cats that were fixed at a later age.
Cats that are fixed while young continue growing for a longer time than do other cats and thus end up larger.
For the record, most cats reach puberty when they are around six months old. Again, there is a range: some cats hit puberty when they are four months old, and some don’t reach it until they are ten months old.
How much should you feed a kitten?
A less benign reason for small size is poor nutrition. Some cats stay small because their owners don’t feed them enough or don’t give them the right food.
Allegro Ringo, who writes for Cuteness, provides a guide on what to feed kittens of a given age and how often to feed them.
Ideally, kittens eight weeks or younger should stay with their mother, as they are not fully weaned.
Somebody who is caring for an orphaned kitten that is under four weeks old should give it kitten formula at least six times a day.
When the kitten is four weeks old, they should give it a gruel that is a mixture of the formula and wet kitten food. A week later, they can introduce the kitten to solid food.
Because it is rapidly growing, a kitten between eight and twelve weeks old will need three times the calories as the average adult cat.
They will need to be given a whole can of wet kitten food every day, and they will need to be fed four times a day.
After the twelfth week, the kitten may need to be only fed three times a day, but it should still be given the equivalent of a can of kitten food every day.
As its growth starts to level off, a kitten’s appetite will become less voracious by the time it is six months old.
Most cats will have finished the bulk of their growth by the time they are a year old, and they don’t need the extra protein and fat in kitten food. They can now be given adult cat food, and they get fed twice a day.
Kittens should also always have easy access to water, which should either be room temperature or cold. They can drink either filtered water or tap water.
Kittens should never be given people food, for it can upset their stomachs. It also doesn’t have the nutrients they need to grow strong and healthy. Neither does dog food.
Is there such a thing as a dwarf cat?
Yes. According to Sarah Hartwell, a writer for Messy Beast, dwarfism describes a group of genetic disorders characterized by stunted growth – and there are at least 200 types. At least half of them are also skeletal dysplasias, which means the cat’s bones also don’t grow or develop normally.
The below video is about Lil Bub, an internet celebrity who has dwarfism:
In both cats and humans, the most form of dwarfism is achondroplasia, which is also known as true dwarfism or chondrodysplasia.
In this condition, the body is normal-sized, but the limbs are abnormally short and often deformed. The head is often oversized with an undershot lower jaw and crooked, crowded teeth.
While the Munchkin cat breed has the short legs associated with achondroplasia, it doesn’t have the oversized head.
Munchkins, therefore, probably don’t have achondroplasia; they probably have hypochondroplasia or pseudoachondroplasia, which are similar types of dwarfism with milder effects.
Cats can also be midgets. These felines have pituitary dwarfism, which is caused by a malfunctioning pituitary gland.
In most cases, the pituitary gland simply doesn’t produce enough growth hormone to ensure normal growth. In a few cases, it does produce the hormone, but the kitten’s body doesn’t respond to it.
A midget cat will have normally proportioned body parts – it will just be a lot smaller than it should be. Midgets also stop growing while still kittens, and many keep kittenish features like extremely soft fur and high-pitched cries.
Hypothyroidism or cretinism, which also affects humans, is caused by a missing or defective thyroid that doesn’t produce enough or any thyroid hormone. While it is usually a birth defect, it can also be caused by an early injury to the thyroid.
A kitten with hypothyroidism will show severely retarded physical and mental development. In addition to stunted growth, the affected kitten will have a pot belly, poor skin tone, a flat and malformed muzzle, and lethargy. The condition has been documented in Abyssinian cats.
What else can cause a cat to be unusually small?
According to Ernest Ward and Catherine Barnette, who are both veterinarians that write for the VCA Hospital website, internal parasites can also impair a kitten’s growth, and a severe enough infestation can be lethal.
Examples of internal parasites that can affect kittens and cats include the following:
Hookworms are one of the more common parasites seen in cats. The worm attaches to the small intestine’s lining and sucks blood.
In the process, it can cause severe anemia. Hookworm larvae either burrow through the skin in the cat’s feet, or the cat may inadvertently ingest it.
There are many different types of tapeworms with Dipylidium caninum being the most common in cats.
While it doesn’t do much harm to an adult cat, it causes a kitten to suffer digestive problems and stunted growth. Cats get this tapeworm by swallowing an infected flea.
Cats can also sometimes be infected by Taenia or Echinococcus tapeworms. Taenia worms can be carried by rabbits, rodents, and some birds.
They thus usually infect cats that hunt and eat their kills. Echinococcus worms can be carried by sheep or humans and sometimes infect cats that live near sheep.
Roundworms live in a cat’s intestines. Its eggs are passed in the feces of an infected cat. A kitten with a large infestation of roundworms will develop a potbelly and suffer digestive trouble and stunted growth.
While heartworms more commonly affect dogs, they can infect cats. They are carried by mosquitoes which will inject the larvae into the cat’s bloodstream while feeding. Heartworm infestation can cause vomiting, weight loss, coughing, and rapid breathing.
Veterinarians can diagnose and treat parasitic infestations. They can also advise owners on ways to prevent them.