Friends of the Riney Canine Health Center,
Thank you for joining our pack! I’m Brian Collins, an extension associate for the Cornell Richard P. Riney Canine Health Center, and I’m pleased to share this month’s “From the Vet’s Desk” monthly health tip with our members.
April showers bring May flowers! All this spring rain has me thinking about water and how it relates to our health. For years we’ve been told that we need to drink eight glasses of water every day. Since our bodies are about 60 percent water, we certainly need to make sure we are drinking enough to meet our needs. However, that recommendation has been revised to a general guideline of 9-13 cups per day with men typically needing more than women, but will also be affected by body size, activity, water content of one’s diet and other variables.
How much water should a dog drink? Fortunately, most healthy dogs just know to drink the right amount of water. If we were to measure how much water a dog (including puppies!) drinks per day we would find that they drink approximately 40-60 milliliters of water for every kilogram of body weight. For example, a 20-pound Beagle (9kg) will drink 360-540ml, which equals about 1.5-2 ¼ cups daily. However, a 150-pound Great Dane (68kg) will need a much larger bowl to contain the 5 ½ to 8 ½ pints he’ll need to quench his thirst every day!
What if your dog is drinking more than this? It may be normal if your dog has always done so, but we can expect them to drink more, for example, on hot days or when they’ve been more active. But what if you’re finding that you have to fill the water bowl more often or that your pup needs to go outside more often than she used to? When a dog drinks more than normal we call it “polydipsia” (PD) and the resulting increase in urination is called “polyuria” (PU). When veterinarians are presented with a dog with increased drinking and urination, we abbreviate it in their medical record as “PU/PD.” Officially, a dog is polydipsic when their water intake exceeds 100ml per kilogram, so that Great Dane would now be drinking 14 pints – that’s 1 ¾ gallons per day!
Now most of us don’t routinely measure how much our dog drinks on a daily basis, but we tend to have a rough idea of how often we have to fill the water bowl and how often they need to go outside every day. It can be more challenging if other dogs (or cats) in the household share the same bowl, but you may become suspicious if you find the bowl empty or if your dog is drawn to other sources of water as in the bathroom or outside like puddles. Your dog may be asking to go outside more often to urinate, seems to take longer to urinate, has accidents in the house, or leaks urine while sleeping.
There are many possible causes for a dog that appears to be PU/PD. In most cases, the underlying condition causes an increase in urination which then leads to an increase in thirst.
Some of the more common conditions include:
However, there are some conditions where increased water intake is the primary problem, which then results in the need to urinate more:
If you suspect your dog is drinking or urinating more than usual, we recommend that you schedule an appointment with your veterinarian for an evaluation. Your veterinarian will do a thorough physical exam, ask a number of history questions including what your dog is eating and evaluate any medications your dog is receiving. In some cases, the diagnosis may be relatively straightforward, while with others, more advanced testing may be necessary. Initially, a series of tests will be performed that may include:
Until your dog has been assessed, it should be assumed that your dog needs the water; restricting access can lead to dehydration or dangerous electrolyte abnormalities. Other recommendations include ensuring all water bowls are clean and fresh and offering additional water bowls to ensure that all pets in the household have all they need. More frequent trips outside will help keep your dog comfortable and reduce accidents in the home.
Speaking of water -- let’s not forget that warmer temperatures mean swimming! Here are some safety tips to keep in mind as your dog heads to the local swimming hole!
Dr. Brian Collins, D.V.M. ‘94extension veterinarian
Cornell Richard P. Riney Canine Health Center