How can an owner tell when his canine or feline companion has incurred body water loss that can manifest as health problems? What measures can owners take in preventing their pets from becoming dehydrated?
As a veterinarian practicing in warm and sunny Southern California, I know the important role hydration plays in promoting my patients's best health. Water makes up 70-80% of a dog or cat's body mass, so it's an crucial nutrient to maintain normal cellular function. A loss of only 10% of the total body fluids can cause serious illness.
Symptoms of Dehydration
Dehydration is a diagnosis that is often seen in conjunction with other ailments, including kidney and liver disease, infections, immune system disorders, cancer, and more. There are many clinical signs of dehydration in pets, including: Lethargy Less water available to help cells normally function leads to a pet acting more fatigued and having exercise intolerance.
- Decreased appetite. Dehydration causes reduced blood flow to the digestive tract, therefore less involuntary muscular contraction occurs in the stomach and intestine. With the slowing of the digestive tract, there's an associated reduced interest in eating.
- Fewer trips to the bathroom. Less water being consumed or more water being lost reduces urine and fecal volume and frequency, as moisture is being preserved to help the body to continue to function.
- Water-seeking behavior. Dehydration will cause your pet to seek water from both familiar and unfamiliar places, which could harbor toxins, infectious organisms, or other potentially dangerous substances.
- Sticky, pale gums. When evaluating a pet's oral mucous membranes (gums), the normal appearance should be vibrant pink and moist. When dehydration occurs, gums become tacky (sticky). Additionally, when the gums are firmly pressed to push out blood, the capillary refill time (CRT, or time it takes for blood to refill tissue) is delayed. Normal CRT= 1-2 seconds. Delayed CRT is two seconds or longer.
- Less skin flexibility. Our pets' skin should be soft and pliable, but when enough body of water is lost, skin becomes more rigid. This is called increased skin turgor, which manifests as a lack of ability for skin to retain its normal shape. The area between the shoulder blades ("scruff" or nape of the neck) is a common place when this phenomena can be seen in a dehydrated pet. Try the skin turgor test at home.
- Elevated heart rate and breathing rate. When a pet is dehydrated, the blood becomes thicker and doesn't efficiently flow around the body. As a result, the heart contracts more quickly in effort to deliver nutrients and oxygen and remove metabolic wastes from body tissues. Respiratory rate also increases in attempt to bring more oxygen into the body. Normal heart rate is 70 - 160 beats per minute for most dogs (smaller dogs have faster heart rates) and 160 - 240 beats per minute for cats. Normal respiratory rate is 10 - 30 breaths per minute for most dogs (smaller dogs typically breathe faster) and 20 - 30 breaths per minute for cats.
- Reduced body temperature. Deficient body water also causes blood to have reduced flow to the colon/rectum and ears, which are the two most common places where dogs and cats have their temperatures taken. Normal body temperature for dogs and cats is between 100-102.5 F. Body temperature below 100 F can indicate dehydration in some pets.
How Can I Help My Pets Stay Hydrated?
Be aware of your pet's daily hydration needs. The average healthy dog or cat needs 1 ounce of water per pound of body weight every day.
Provide a clean, fresh, room-temperature water source with the same level of purity that you drink. Why would you consider letting your pet consume water you wouldn't consume yourself?
Prevent your pet's access to water sources potentially having microorganisms or toxins capable of causing mild to severe illness. Puddles, communal water bowls (dog park, daycare, etc.), still bodies of water, and Christmas tree containers should be avoided.
Use pet fountains or circulating water dispensers to promote a pet's curious interest in drinking.
Feed your pet a moist diet. Human-grade diets like home-prepared or commercially available rehydrated options (The Honest Kitchen, etc.) should be chosen over canned options containing moistening agents (carageenan, propylene glycol, etc.). Most canned foods are closer to the format in which nature intends food to consumed as compared to dry foods (kibble), so feeding canned over kibble is my suggestion if home-prepared or rehydrated commercial options are not available.
Minimize your pet's time spent exposed to extreme heat and sun. Seeking shade and cool will reduce the volume of body water that evaporates from the respiratory tract (lungs, trachea, etc.), paw pads, skin, and other body parts.
Coerce your cat to drink with broth or tuna-water cubes. Cats are notoriously challenging to coerce to eat and drink in times of illness or injury. Adding low-sodium broth (chicken, beef, etc.) to foods, giving a goat milk probiotic beverage (Honest Kitchen Pro Bloom, etc.), and offering treats of frozen tuna water (can of tuna pureed with water in a blender then frozen and served as individual cubes) are means of motivating your cat to consume more liquids.
As water is such a vital component of all cells and an essential nutrient for life, it's crucial that all had owners take everyday measures to promote hydration and prevent dehydration.