How much water do dogs need a day?


Many dogs seem to drink a lot of water each day. Cells and organs in the body contain about 70% water, making it the main body component. Without sufficient water to drink, a dog will dehydrate and in time organs will fail and the dog will die.

The importance of water

Water in the body performs many different functions. It helps carry and move important nutrients into and out of cells in the body. It is the major component of blood helping move chemicals, nutrients, oxygen and carbon dioxide around the organs and body. Water is important too for digestion, to help food absorption and for kidney function with the flushing of unwanted chemicals from the body. Water in joints cushions them and makes movements easier. Finally, water cools the dog’s body down through panting and sweating so it can maintain its normal body temperature.  Dogs need to drink more water during hot weather as they lose it when panting.

The daily quantity of water for a dog to drink

There is no precise amount of water a dog should drink each day, but as a general rule a dog eating dry pet food will drink about 30-50ml per day per kg of bodyweight.  Therefore, for example a 10kg dog is expected to drink between 300 and 500ml of water per day.  There are several factors that can change the daily water quantity.   A sedentary dog in a cold environment may drink a bit less. A dog that eats only wet foods including canned food and fresh meat may drink less than the one eating dry pet foods.  This is because canned pet food contains about 80% water compared with dry food which contains about 10% water.  Dogs that are in a hot environment or do heavy exercise, either of which will cause them to pant to maintain body temperature, may need to drink significantly more water than average to help replace the water lost in keeping them cool.

Maintaining a healthy water intake

Most dogs are very good at drinking sufficient water, and the best way to help your dog is by making sure that fresh clean water is always available for them to drink. Replenish with fresh water daily and ensure the water bowl is cleaned regularly. If you are out for a long time with your dog, either take water or ensure your dog has the opportunity to drink. If the dog either drinks too much or too little it can indicate an underlying illness and you should seek veterinary help for your dog if you are concerned. To look for dehydration in your dogs, pinch a piece of skin at the back of your dog’s neck, stretch it out and then let it go. A correctly hydrated dog’s skin will shrink quickly back into place, while the skin of a dehydrated dog will return only slowly. You can also check your dog’s gums for dehydration – wet, slippery gums are healthy while dull or sticky gums suggest dehydration. You can try to measure your dog’s water intake yourself by using a water bowl and measuring the difference in quantity of water in and out of the bowl daily.  It is best to measure this over a few days and average the values to get a more accurate result as most dogs are quite messy drinkers!


Dr Peter Messent

23 May 2017

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