Expert: Jessica - 8/1/2011

Question
Hi Jessica

My neighbors who own several cats that are about 2 years old have one cat that is extremely thin.  I gave him some food a few minutes ago and he seemed to be starving.  He is so thin in comparison to his other siblings?   Do you know of any reason why this one cat is so thin and starving while the others are not?   I sometimes give the others all of them a bit of wet food, but today it became clear to me that this one skinny cat was too hungry.  When I came out with food, the others ran off but the skinny one did not.  After I backed off a bit, the others came to eat also.

Answer
Hi Gina,

There are some medical conditions that can cause a cat that is well-fed to feel hungry all the time and continue to lose weight. In a cat around two years old, the most common reason is a parasitic worm infestation. Tapeworms, transmitted by swallowing infected fleas or, less commonly, by eating infected prey, live in the intestines and glean nutrients from the cat’s food. Because the cat is not receiving all of the nutrition the food provides, he will be constantly hungry and will lose weight. Another kind of parasitic worm, roundworms, also live in the intestines and feed off nutrients in the cat’s food. These cause malnutrition in two ways. They take away nutrients from the cat’s food, and they can also cause severe diarrhea, leading to weight loss over time. There are dewormers for both types of worms available at pet stores, but they must be purchased separately (a combination dewormer is available by prescription from the vet). Also, because tapeworms are spread through fleas and roundworm eggs are abundant in the soil, it’s important to keep outdoor cats protected against these parasites regularly. Your neighbor can prevent these pests by using a medication like Revolution, available through their vet.

However, there are some other conditions that even young cats might suffer from. Chronic diarrhea or vomiting are suspects when a young cat has a poor body condition. Since this cat probably uses the outdoors for elimination, monitoring his stools will probably be difficult. But your neighbor would be best to try to keep him in for a few days to do just that. If he has runny stools, or just the opposite – very large, formed stools – this can tell the vet something about what’s going on. Diarrhea is usually treatable with an antibiotic/antiparasitic medication. Very large stools can indicate that the cat might have a pancreatic insufficiency, so his food is not being digested well. In essence, he is slowly starving because his body cannot derive the nutrients it needs from his food. Digestive supplements can usually help with this.

It could be possible this kitty, and even the other kitties, have a terminal virus such as the feline leukemia or feline AIDS viruses. Cats infected with these tend to appear normal for most of their lives, until they reach the terminal stages. For the feline leukemia virus, this is usually around 2 to 3 years after infection. For the AIDS virus, this can be 2 years or 15 years down the road. During the terminal stage of the diseases, the cat is usually suffering from either cancer or organ failure, or both. Here, we see the kitty lose weight drastically. At first, the cat may maintain a healthy appetite, but it will soon suffer. The viruses are incurable and fatal. There are tests for these diseases that can be run right in the vet’s office. If this kitty happens to test positive, all the siblings should be tested, as well. The diseases can be spread through bite wounds, and leukemia can be spread through other close contact, like mutual grooming.

While uncommon in young cats, an overactive thyroid, diabetes and kidney disease are all possibilities, as well. These are most often seen in cats at least six years of age, but sometimes we find them in younger cats, especially kidney disease. They cause hunger and weight loss for different reasons. A simple blood panel will check all of the values necessary to determine whether any of these are a concern for this kitty. If so, there is a pill or ear cream to help control thyroid function, insulin and/or a special diet to help manage diabetes, and a special diet to slow the progression of kidney disease.

This list isn’t exhaustive, and there are other less common causes of drastic weight loss.

I hope that helps! Bless you for helping this poor little guy.

Jessica