How much water should my pet drink?

What about pets? Should owners try to encourage dogs and cats to drink more water?

I am often contacted by owners who are concerned that their animals are not drinking enough. Most of us can drink a pint of cool water ourselves, but trying to force an animal to do the same is not easy. Should they try this?

The answer is a definite no.

The living body does an excellent job of ensuring that optimal hydration is continuously maintained naturally. If dehydration develops for any reason, the animals are thirsty.

For healthy pets, all you need to do is make sure your pet has access to fresh water at all times. Their own thirst, driven by their body’s natural needs, will do the rest.

The situation is different for animals that are not feeling well: some illnesses cause dehydration and sick animals may not be able to drink enough to meet their optimal needs.

Examples include severe gastroenteritis, animals in shock and certain metabolic diseases such as unstable diabetics or animals with kidney failure. Pets with these conditions who have become dehydrated will be visibly ill: dull, weak and unappetizing.

Any animal showing these signs should be taken to the vet urgently, and then the best treatment can be given.

If an animal is significantly dehydrated, intravenous fluids, given as a drip into the animal’s paw, will often be recommended. This cannot be done all at once: the animal will usually need to be left at the veterinary clinic to be rehydrated for several hours or more, with fluids being administered in carefully measured amounts via an electronic pump. This treatment saves the lives of many seriously ill animals.

Oral rehydration is sometimes used when pets are less severely ill, such as dogs with mild bouts of vomiting and diarrhea, with electrolyte-enriched fluids dispensed.

However, it is still a gentle encouragement to drink, rather than forcing syringes of liquid. It’s too easy to hurt.

If an animal refuses to take liquids and struggles, the liquid may spill the wrong way down the back of the throat and then be inhaled into the lungs rather than swallowed into the stomach.

It makes more sense to try to make the drink as appealing as possible, instead of using brute force.

Several waterers in different parts of the house, cleaned and replenished daily, can help.

Fountains for cats, whose water is constantly recirculated thanks to a small electric pump, create the impression of flowing, moving water, which some animals seem to prefer to drink.

Also, even simpler, try adding extra water to your pet’s feeding bowl. Dogs and cats often like to lick their clean bowls, and they’ll barely notice if you’ve added a little extra liquid to dilute their daily meals.

You can also purchase a commercially produced rehydration fluid fortified with chicken extracts to make it palatable to dogs and cats.

If you’re worried, it’s worth monitoring your pet’s urination: if he urinates regularly, he’s likely to be reasonably well hydrated. One of the main signs of dehydration is greatly reduced urine production.

Although veterinarians aren’t usually concerned about pets not drinking enough water, it’s a different story if a pet starts drinking excessive amounts of water.

This is a key measurement that is often the first sign of a wide range of common illnesses, from diabetes to kidney disease to a range of hormonal issues.

There is a well-known figure that veterinarians use to judge whether or not an animal drinks a disturbing amount: 100 ml per 1 kg of body weight. So if a 5 kg cat drinks more than 500 ml, or a 20 kg dog drinks more than two liters, it is a sure sign that something is wrong.

If your pet starts drinking more than usual, measure the precise amount, recording how much you put in their bowl, then noting how much is left a day later. Remember that wet pet food contains significant amounts of water when doing these calculations.

If you find out that, yes, they are drinking too much, collect a urine sample and go to your local veterinarian. A blood sample will likely be needed, and soon enough the vet should be able to tell you why your pet is so thirsty and what needs to be done to help.

Getting that urine sample isn’t always easy: the easiest way is to use some shallow tupperware, follow your dog around the yard, pinch him with the receptacle at the crucial moment.

Most dogs that drink more than usual also urinate more, which at least makes this task easier.

It’s trickier with cats: the easiest answer is to ask your vet for some special glass beads and use them to replace your cat’s normal litter substrate in his box. When they pass urine in the litter box, it can then be drained into a clean container to take to the vet, leaving the beads behind.

A pet’s drinking water is an important aspect of its life, and for your pet’s health, it is worth monitoring this carefully.