Calculate how much water your cat needs
The amount of water a cat should drink depends on the type of food consumed.
A cat requires a total of 44 to 66 ml of water per kilogram of body weight (or 0.67 to 1 oz. per pound) each day.
(source: “Feline behavior for veterinarians” second edition, B. V. Beaver, 2003)
The above includes any amount of water that the cat obtains through its consumption of food, which will differ significantly by the type of food eaten. Your typical dry cat food, for instance, is approximately 8 to 10% water, whereas wet canned food may be as much as 80% water.
Calculation Example:
Let’s say that we have a cat weighing 5 kg (11 lbs.). This cat’s minimum daily water requirement, when ran through the above formula, is 220 ml (7.4 oz.).
If this cat eats 80 grams of dry food per day, the diet provides a mere 8 ml (0.3 oz.) of water, meaning the cat should drink an additional 212 ml (7.2 oz.). This total is very close to the total minimum water requirement. This makes sense since dry food is, well, dry.
If the cat receives 250 grams of canned food per day, the food provides 200 ml (6.7 oz.) of water. This means the cat only needs to drink as little as 20 ml (0.7 oz.) of fresh water; four teaspoons.
The above example perfectly illustrates how the type of food can be a cardinal influence when considering your cat’s drinking regimen. Note that this amount will also depend on your cat’s overall activity and health, the weather, and other conditions. However, we can conclude that how much your cat should drink is less important than the type of food he or she eats.
How to know if your cat is getting enough water
Cats naturally drink very little because their bodies have adapted to extract body fluids from their prey, and they are also able to sustain themselves during short periods of draught with ease. However, if your cat continually drinks little to no fresh water, he or she runs the risk of becoming dehydrated. This risk exacerbates if your cat consumes only dry food.
If the opposite happens and you notice that your cat is drinking far more fresh water than usual, visit your veterinarian as soon as possible.
How do you measure your cat’s water intake? You can approximate the amount by checking your cat’s water bowl each day. Keep in mind that dry indoor air may cause much of the water to evaporate. This method of measurement falls flat if multiple cats share the same bowl.
The best way is to check your cat’s hydration and health. Does this require a visit to your vet? While you should take your cat to visit your veterinarian at least once a year for checkups, you can check your cat’s hydration level at home.
The simplest method is to test your cat’s skin elasticity. Pinch between your cat’s shoulders, gently pull the skin upward, and then release. If the skin takes longer than a full second to go back in place, you have cause for concern. You can learn more about signs of dehydration in cats here.
Visit your veterinarian if you even suspect that your cat might be dehydrated. Cats are very slow to develop visible signs of dehydration, and in turn, take a long time to recover. In most cases of dehydration, additional fluid administration will be required.
To prevent any further issues, be sure to change out the water frequently, add more bowls in separate locations, and switch him or her to a diet of wet food. Learn about ways to get your cat drinking more water here.