Written by Shannon Fujimoto Nakaya, DVM
Water is essential for life. Most mammals, including humans, can go on hunger strike for days and longer before dying of starvation (mind you, starvation is still not at all desirable for maintaining a body, particularly an older or more fragile one); however, water strike or water deprivation for even one day will begin to damage and destroy a body.
Fluids keep the body lubricated and working. Fluids are essential for blood flow and circulation. Fluids flush metabolic waste products and toxins out of the body. Fluids need to replenished daily.
The average healthy cat or dog will drink roughly 1/2 to 1 ounce (15 to 30 ml) of water per pound of body weight per day. So a 10 pound cat would drink about 3/4 cup of water daily. Or a 30 pound dog would drink about 30 ounces (1 liter). Notice that I've italicized the "roughly." Pets that eat moist food will consume less water than pets that eat dry food. Pets that live in warmer and drier climates will typically drink more than pets that live in cooler climates. Certain conditions -- diabetes, hyperadrenocorticism (Cushing's), aging kidneys, kidney diseases, fever, panting, and certain medications for example, can increase daily water requirements. Your veterinarian can help you calculate how much water your individual pet's daily water requirements.
It can be helpful to quantitate how much water your pet consumes in a 24 hour period. To do this, you measure how much water you put out for the pet, and how much is left after 24 hours, and do the math. Doing this for several consecutive days gives you a pretty good idea how much water your pet consumes on the average day. As a veterinarian,I often use this information to help me decide if a pet has a medical condition that I should be concerned about.
There are several ways to assess hydration in your pet:
- Their gums should be moist, kind of like ours. "Cotton mouth" can be a sign of dehydration.
- The frequency and volume of urination will decrease. Keep in mind that animals will still continue to produce urine even when dehydrated. But if your pet usually pees three or four times a day and hasn't urinated in 18 hours, that's an indicator of dehydration.
- The color of the urine may become darker, though not always.
- The odor of their breath will change when they are dehydrated. It's hard to describe the particulars of uremic bad breath, so you'll just have to get used what your pet's breath usually smells like and then you'll at least know when it's not right.
- Your pet's fur should rest smoothly over it's body and move fluidly when your pet moves. When there is more fur that's "out of place" than usual, it can indicate changes in hydration.
- Decreased skin turgor is often used to assess hydration. When you "tent" the skin by gently lifting it away from the body (usually this is done in the area of the shoulder blades), and then release it, the skin should instantly drop back into place. If it slowly goes back down, or stays tented, that is an indicator of moderate or severe dehydration.
- Eyes will appear more sunken in dehydrated patients.
- Dehydrated patients pretty rapidly start to feel noticeably lousy and their energy declines.
Any combination of these signs warrants immediate attention. Dehydration complicates recovery of any conditioin. Mild dehydration can be addressed on an outpatient bases. Moderate dehydration will land a patient in the hospital. Severe dehydration can lead to organ failure and sometimes irreversible organ failure.
Sometimes our animal companions naturally increase their water consumption according to their needs. And sometimes they need to be enticed, encouraged, or "tricked" into lapping up enough fluid to maintain hydration.
Tips for encouraging water intake:
- Variety of water bowls and locations.
- Some pets are enticed by flowing water -- the chronically dripping faucet works but can be wasteful and expensive. There are several fountain-style pet waterers on the market.
- Canned food has a much higher water content than kibble.
- Additional water can often be added to canned food making it the consistency of a stew or soup.
- Water can flavored with small amounts of milk, tuna juice, or chicken broth -- ie. making "tea."
- Some animals will take water dropperful by dropperful or syringe by syringe.
- Subcutaneous or SQ fluid administration is a technique where small boluses of sterile fluids and electrolytes are administered under the skin via injection or via implanted catheters. Some caregivers become comfortable doing this on their own after being taught by their veterinarian, while other caregivers prefer to leave it to their veterinarians or veterinary nurses to provide this service.