How Does Kidney Disease Affect Dogs & Cats?
Kidney disease frequently arises in older cats and dogs. Kidney failure can develop in young animals, but it is far more common in pets over age 10. It is the leading cause of death in older cats.
In the Pet Food Recall of 2007, melamine contamination of pet food caused tens of thousands of cats and dogs to develop Acute Renal Failure (ARF). Many of the pets who got sick but recovered likely suffered some kidney impairment, and may have ultimately developed Chronic Kidney Disease (CKD). In that case, age made no difference; animals of all ages were affected.
The kidneys filter out and excrete toxins from the body through the urine. Healthy kidneys conserve water and concentrate toxins into a smaller amount of liquid to be urinated away. The kidneys have a very large reserve capacity, and symptoms of failure are not seen until approximately 75% of kidney tissue is nonfunctional. When the kidneys are damaged, they become less able to concentrate the urine. Because they’re losing water in the urine, they need to drink more—but because they’re drinking more, they urinate more. So, the first and most noticeable symptom is usually an increase in water consumption and urination ("drink-a-lot, pee-a-lot syndrome").
As the kidneys lose function, other signs of CKD may occur, such as weight loss, nausea, constipation, low energy, fatigue, and poor appetite. A blood test and urinalysis should be done by your veterinarian if you notice these symptoms, as there can be many reasons for such symptoms. A blood test and urinalysis are necessary to accurately diagnose CKD.
The measurement of urine concentration is called Urine Specific Gravity (USG). If the USG is low (less than 1.035 in cats, and 1.030 in dogs) and there are abnormal levels of two other compounds, then kidney function is reduced. The first, BUN (blood urea nitrogen), may be high if the animal is dehydrated, or eats a very high protein diet. However, as long as the kidneys are able to concentrate the urine, small elevations in BUN are usually not a cause for alarm. The second is a protein called creatinine. Creatinine is a more sensitive measurement of kidney function; an increase in creatinine usually means that the kidneys are having a difficult time. In advanced disease, an increase in phosphorus is also seen, and indicates that 85% of kidney tissue is damaged.
Naturally Supporting Dogs & Cats with Chronic Kidney Disease
No conventional or alternative medical approach can reverse CKD, since the disease involves the death of kidney cells and replacement by scar tissue. The rate of progression in any individual pet may be slowed, but not stopped, by various methods. When the process is advanced, the kidneys become scarred, small, and lumpy, and the amount of functional tissue is greatly decreased. The most significant effects caused by the loss of function are build-up of blood toxins, and anemia. These can cause weight loss, lethargy, vomiting, loss of appetite, weakness, and other signs of illness.
Some of the best and simplest approaches include:
Does Too Much Protein Cause Kidney Failure in Dogs & Cats?
You may have heard that restricting protein is recommended for pets in kidney failure. This has been the "standard" approach for decades in dogs and humans. However, in cats, it remains controversial.
The real culprit is not protein but phosphorus, which combines with calcium and gets deposited in the kidneys, causing further damage. Meat contains a lot of phosphorus, so the easiest way to restrict phosphorus is to restrict meat protein. Decreasing phosphorus intake (by restricting protein) can help some pets feel better, so it may be worth a try if the symptoms are bothersome.
However, some studies have suggested that excessive restriction of protein in cats may actually cause further damage to the kidneys and other organs, because there is not enough protein for normal body maintenance and repair. Experts say that these diets are not appropriate for cats until the BUN (Blood Urea Nitrogen) is at least double what it should be normally (about 60-80 mg/dl), and should never be fed to kittens or healthy cats.
For many animals, a diet with HIGH QUALITY protein will be better than a low-protein diet. Low-protein diets, if not carefully managed, can lead to malnutrition. If a low-protein diet is necessary, bear in mind that non-prescription canned foods are much higher in protein than similar dry foods.
Canned foods typically contain higher levels of protein than dry foods. Since dogs are more omnivorous and are better at keeping themselves hydrated than cats, they may do well with mostly dry food.
Over-the-counter canned foods vary tremendously in phosphorus content, from less than 150 mg to over 600 mg! Veterinary low-protein diets are severely restricted, containing less than 100 mg of phosphorus per 100 Calories.
Since dogs are more omnivorous and are better at keeping themselves hydrated than cats, they may do well with mostly dry food. For dogs, foods containing more vegetables and less meat will contain less phosphorus.
Because water balance is so crucial to cats, it is best to feed them a high-moisture diet to help support hydration levels. Do not feed cats only dry food. Feeding mostly or only canned, raw, or homemade food, even though they tend to be high in phosphorus and protein, provides the moisture and calories they need, in a very palatable form that most cats will happily eat. Adding egg whites, which contain very little phosphorus can provide extra protein without causing harm. Dry cat food causes dehydration even in healthy cats, and may not be appropriate for CKD cats.
"...a diet with HIGH QUALITY protein will be better than a low-protein diet."
Nutritional Supplements To Help Support Dogs & Cats with Kidney Disease
Several nutritional supplements may help maintain normal kidney function. Omega-3 fatty acids have been shown to be beneficial in CKD. Be sure to select a product that contains only omega-3 (pets get plenty of omega-6 in their food), that is free from contaminants, and doesn’t come from farmed fish such as salmon. I recommend the following:
- Nordic Naturals Omega-3 Pet
- Only Natural Pet Wild Alaskan Salmon Oil
- Nature’s Logic North Atlantic Sardine Oil
B-vitamins help the animal manage normal stress and supply essential nutrients. Many animals can also benefit from antioxidants, such as vitamins C and E. Potassium supplements may be needed, especially for cats. Kidney support supplements, like Renal Essentials by Vetriscience (for dogs or for cats), can be great all-in-one supplements that contains herbs, Omega 3 fatty acids, and vitamins B and C.
Recent research shows a benefit from probiotics (friendly bacteria) in cats with CKD. Kidney blood values (BUN and creatinine) decreased significantly when cats were given probiotics in canned food.
A newly published paper suggests that melatonin could be helpful so support normal function and health of the kidneys. However the study was done in rats, and appropriate dosages for pets are still unknown. As new information becomes available we’ll post updates on our Only Natural Pet Blog, so check back often!
A nutritional supplement called "Renafood" from Standard Process helps support normal renal function and kidney detoxification. Most pets eat them readily if they are crushed into powder and mixed with canned or homemade food.
Always consult with your veterinarian before starting your dog or cat on any new herb or supplement when dealing with kidney disease.
Supplemental Fluids for Dogs & Cats with Kidney Failure
Your veterinarian can give your pet subcutaneous fluids in the clinic, or teach you how to give them at home. This is the least intrusive and most beneficial support you can give your pet. Animals in renal failure drink a lot of water, but they cannot drink enough to compensate for the loss of water through the kidneys. Subcutaneous fluids are an excellent way to help support hydration levels and make your pet feel better. (Click here for detailed instructions)
Holistic Veterinary Care for Kidney Failure
While nothing can create new kidney cells when scar tissue has already formed, homeopathy, herbs, flower essences, or acupuncture may help provide nutrients for a healthy body. Check out the American Holistic Veterinary Medical Association for a directory of holistic veterinary practitioners by state.
It may be helpful to lessen stress for any animal with kidney disease. Quality of life is an important consideration when deciding how aggressively to approach any disease. Flower Essences can help maintain normal emotional balance and manage normal stress. I recommend the following formulas:
- Only Natural Pet Just Relax
- SpiritEssence Graceful Aging
- Pet Essences Kidney Strengthener
As the disease progresses, consultation with a holistically trained veterinarian is recommended for proper use of appropriate herbal remedies.
Traditional Chinese herbal formulas like Golden Book Teapills, are a classic combination of herbs used to help maintain normal kidney function.
Acupuncture may also be useful to support normal function and health of the kidneys. To find a practitioner in your area, visit the International Veterinary Acupuncture Society.
Information in this article is not intended to diagnose, treat, or cure your pet and is not a substitute for veterinary care provided by a licensed veterinarian. For any medical or health-related advice concerning the care and treatment of your pet, contact your veterinarian.