The Truth About Cat Pee


Editor’s note: Have you seen the new Catster print magazine in stores? Or in the waiting area of your vet’s office? This article appeared in our March/April. 2017 issue. Click here to subscribe to Catster and get the bimonthly magazine delivered to your home.

We’re repulsed by it. When we see it on a toilet seat in a public restroom, we promptly pivot out of the stall in search of a cleaner commode. I’m talking about urine. Humans are disgusted by it. But animals have a different relationship with urine.

In fact, cats communicate with their pee. They mark their territories’ boundaries with it. Males announce to females that they are ready and available to mate and warn other tomcats to back off with their urine.

Urine also says a lot about the health of individuals, so it’s no wonder human doctors and veterinarians examine it to detect disease. There’s a lot more to urine than meets the nose.

It starts with water

All living things need water to survive. Water regulates body temperature, carries nutrients and oxygen to all the body’s cells and flushes out waste. An organism’s major systems need water to function properly. In general, the amount of urine cats produce depends on how much water they drink.

Just as some people drink more water than others, so do some cats drink more than others. As carnivores, cats in the wild are accustomed to consuming much of their fluids from their prey. But dry cat food is only about 10 percent water, so cats who feed on mostly kibble will need to drink a lot more water throughout the day. Canned food is around 80 percent water, so cats who eat this type of diet will likely drink a lot less water, because they’re getting it in their food.

Photo by Shutterstock

Provide clean, fresh water for your cats every day. Check to make sure they are drinking the water, too, especially if they eat an exclusively dry food diet. If your cat likes to drink running water, provide a fountain. If your cat likes extra cool water, try dropping an ice cube in the water, especially on hot days.

Drinking water doesn’t directly produce urine, but it does optimize the urinary tract’s efficiency. The water mammals drink goes through the digestive tract and is absorbed into the bloodstream. The kidneys, which are part of the renal system, or urinary tract, filter the blood

The uniqueness of cat pee

Cat urine contains about 95 percent water and 2 percent urea, which is a waste product resulting from protein metabolism in mammalian urinary tracts. Cat pee also contains trace amounts of chloride, sulfate, phosphate, sodium, creatinine, ammonia and uric acid. Normal cat urine is clear and yellow to amber in color. Certain medications can cause urine to turn bluish, pinkish or other colors. Blood turns urine dark red or brown, and liver problems produce urine that is greenish, yellow-brown or foamy. Take your cat to the vet if you notice these abnormal urine colors.

Cat urine has an odor like no other. That’s because, as cats are carnivores, cat urine contains high levels of protein. The building blocks of protein are amino acids. Cat urine contains an amino acid called felinine, which is unique to felids. Although felinine is odorless to humans, it breaks down into volatile sulfur-containing compounds that produce pungent odors, which are also unique to felines. Intact males produce about three times more of it than neutered males or females, because testosterone regulates felinine excretion. These odors serve as territory markers and female attractants.

Cat spraying by Shutterstock

Since cats use urine to communicate these important messages, they are not as intent on removing those messages as we are. Cat urine odors are difficult to remove for two reasons.

One is that cats have a superior sense of smell, so they will be able to pick up on the pheromones left behind from the felinine that we cannot detect.

Two is that these volatile sulfur-containing compounds are not eliminated by regular cleaners. Keep in mind that these compounds remain on outdoor surfaces come rain, wind or shine.

Fortunately, certain enzymes can break down cat urine compounds, even those only detectable to kitty. Cats will continue to mark the spot if we don’t completely eliminate all odors, so use an enzymatic cleaner.

The feline urinary tract

In mammals, the urinary tract consists of:

  • Two kidneys, which filter blood and produce urine
  • Two ureters, which carry the urine to the bladder
  • The bladder, which holds the urine
  • The urethra, a tube through which urine flows from the bladder and exits the body

When the kidneys stop working correctly, waste products can enter the bloodstream. This can compromise the body’s other vital organs and cause severe and even fatal illness. If your cat is not urinating, seek emergency veterinary care. Kidney failure,

a urinary blockage or ruptured bladder can cause urine flow to stop. If your cat produces too little urine in a 24-hour period, that could indicate dehydration, kidney failure or a urinary blockage. If your cat produces too much urine, diabetes or other illness might be the culprit.

The Cornell Feline Health Center reports that more than 30 percent of cats will get kidney disease in their lifetime. It’s an affliction that especially affects older cats, as more than half over the age of 15 have a form of kidney disease. Fortunately, veterinarians today can detect the chronic form of the disease early and slow its progression. Chronic kidney disease has no cure, but cats can live a quality life with proper diet and treatment. Acute kidney disease can occur if the cat ingests a toxin, experiences a urinary blockage or has untreated dental disease.

Photo by iStock

Different types of peeing

Cats like a clean bathroom as much as we do, so if they’re peeing outside the box, something might be amiss. Consider these different types of pee postures.

Marking is usually done vertically to let other cats know that this is the boundary of another cat’s territory. If you see pee on vertical surfaces, suspect that other cats are around and your cat is communicating with them, be they neighborhood cats or a new cat in the household.

Nervous peeing usually happens when the cat becomes anxious and can’t make it to the litter box. This type of peeing might be a call for help to the cat’s favorite human and usually appears on horizontal surfaces.

Normal peeing is what most spayed or neutered cats will do as long as they have a clean litter box and a home they perceive as safe.

Who knew?

Who knew that urine could reveal so much? The next time you see it, relax, as most urine is considered sterile, meaning it contains no bacteria, viruses or fungi. Pay attention to the color, both yours and your cat’s, and take your kitties to the vet for a wellness check that includes a urinalysis annually or twice a year for seniors.

About the author: Susan Logan-McCracken and her husband are brushing their two cats, Sophie and Maddie, more regularly now that they have found a brush that their kitties love. Their Southern California home has less cat hair floating around in it now.

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