Routine Maintenance of Cats

Calculating water intake for cats

Question: Dear Dr Mike,

I have read the September issue of VetInfo Digest. I would like to ask, for cats, how much water intake and how much urination per day should be regarded as PD/PU?

Thank you very much.

Regards, Ernest

Answer: Ernest-

There are several ways to estimate the water intake needs for cats and to determine if they are drinking more than normal.

Most animals require approximately the same amount of water intake as calorie intake on a daily basis. To determine the necessary calorie intake for a cat, the formula is 1.2 x the resting energy requirement (RER), which is roughly 1.2 x 70 calories/kg of body weight. Using this formula, an 11 lb cat (5kg) would need 420 calories per day and therefore about 420ml of water. Some water is obtained through the food and the amount varies by composition of the food (canned food might be 80% water and dry food 5% water, for instance). The variability in water need based on diet can be very large and is a source of confusion. Cats being fed dry food are reported to require approximately 2.5 x the volume of dry food for water intake. So if the cat is eating 1cup of dry food per day it requires approximately 2.5 cups of water per day. Cats being fed canned food can sometimes nearly meet their water intake requirements from the food alone.

With these things in mind, the answer to your question from a clinical standpoint comes down to this. If you are observing an increase in your cat's water intake and everything else in his or her life is about the same, there is a really good chance that the problem is polydipsia or a real increase in the need to take in water. This should be reported to your vet and screening tests to rule out the most common problems leading to excessive water intake considered. A urine sample can sometimes rule out diabetes and kidney failure, two of the most common causes. Routine blood chemistry examination and cell counts can help rule out liver failure, kidney failure, diabetes, hypercalcemia and polycythemia as potential causes.

Mike Richards, DVM 12/31/2001

Types of Cat litter - what is safest

Question: Hi - Thanks for providing such a useful site. While I have a wonderful vet for my two cats I appreciate supplementing my information by visiting your site often. I certainly intend to renew my subscription in order to do my small bit to keep you on-line.

My question: What kind of cat litter is the safest for cats? I have recently read articles in the newspaper written by vets in which the safety of clumping litter was questioned. It was suggested that their licking (when grooming themselves) the dust from the clumping litter could cause serious illness in cats using that type of litter. I have two cats, three litter pans, and a serious dust problem; I've searched for a safe product that is low-dust. Do you have any information that could help me? I will subordinate my dust problem to my cats' safety. I am particularly concerned because I recently had one cat die from intestinal cancer and currently have a cat diagnosed with inflammatory bowel disease. Both cats have used clumping litter since it became available. I will appreciate your response. Pat

Answer: Pat-

Every couple of months I review the literature for articles dealing with complications from using clumping litter. To date, the only one that I have found that details a first hand account of a problem with clumping cat litter was in a basset hound that ate most of the contents of a litterpan and did develop a gastrointestinal obstruction as a result of ingesting the litter. The only other problem I have seen mentioned is one reference to clumping litters being more dusty than the low dust litters, making it more likely that an asthmatic cat might have problems with it.

I think that the litter clumping in the digestive tract is an example of an urban rumor. My thinking on this goes this way. First there are no accounts of this problem reported in the veterinary literature that I have access to, other than the one dog. Secondly, in my practice, I think that more dogs eat cat litter than cats. So if this is a problem, why aren't dogs being affected (other than the one mentioned above)? I will continue to check for problems with clumping litter) but for now, I think it is safe.

Cats prefer the clumping litters in tests. Some of our clients with asthmatic cats like to use one of the pelleted litters, such as "Yesterday's News (tm)" or "Pine Step" due to the decrease in dust. As long as the cat is happy with these litters I see no harm in using them if you prefer, as it would help to keep dust down. Some cats are reluctant to use these types of litters because they have developed a preference for the litter they have been using.

Personally, I still prefer the clumping litters at this time.

Mike Richards, DVM 3/28/2001

Do our moods affect our pets - Sleep and cats

Question: Dear Dr. Richards, On January I adopted a four year old female Siamese cat that was in a shelter since September 2000. She is a great cat who is very loving, affectionate and smart. She loves to be with me in bed and preferably touching me, which I love. One question though is I think she may be sleeping a lot and need to ask you how I can tell? I myself have a depressed disorder which I take medicine for and seem to be OK and functioning. There are times when I find myself sleeping more than I should as I can't seem to get motivated. And I wanted to know how my precious cat deals with that type of situation. She knows her way around my large house and is a most talkative cat. The last cat I had named Ollie seemed to be the same way except he found stuff to do in the house, as I have set up ladders, cat nappers and games to play.

I wonder if this is an issue of my depression, or KITTY merely just wanting to hang out with me and wanting to get used to her new environment. Since I lost my cat back in August I have been so cautious and never wanted to adopt a cat, because of the hurt the loss caused. But I started doing volunteer work at pet which shelters homeless dogs and cats and Kitty more or less adopted me. This organization will not kill any animals they find and will house the animal until a suitable home is found. They take applications and do a thorough check. The animals also get excellent vet care from prominent doctors in our metropolitan area, which is a blessing.

So again my question is can my depression be transferred to my cat and what are the signs that maybe she is bored by me. And is her behavior normal for a cat that has been with me since 1/11/01. The Vet has checked her out and she had gingivitis, which I wrote to you about, and prescribed ammoxicilin.

Any further questions, please ask so I may provide more data. Thanks so much for your help.

Sincerely, Buddy

Answer: Buddy-

I think that pets are sensitive to our moods because they affect their day, but I don't think that it would be possible to induce depression in pet, so I don't think that you should worry about much about that.

Cats vary in their sleeping patterns, but the upper end of "normal" sleeping times is really high in cats. One study I saw said that cats sleep up to eighteen hours a day and another study said fourteen hours a day. Since both of these figures are higher than most human's sleeping times we do sometimes get the impression that cats are sleeping too much when they are not.

It is a great deal of stress for a cat to be in a shelter. They are not social in the way dogs are and the lack of privacy is hard on a cat. It can take them some time to get over this sort of experience. In addition, cats are highly territorial and I think that they are worried about territorial invasion (either by them or expecting it from someone else) when they first come to a new home, so that adds to the stress. One way that all creatures deal with excessive stress is to sleep a lot, so I would not be surprised if Kitty is still adjusting some and is sleeping more than she will when that process is over. It does not surprise me when it takes one or two months for cats to adjust to a new home, especially cats who have been through more than one home in the past. As long as she seems OK otherwise, I don't think I'd get too concerned for a little while longer.

Mike Richards, DVM 2/10/2001

Assessing cats age

Q: Just had a male (un-neutered) cat adopt me. Was wondering how you could tell the age? He obviously isn't a kitten, but still seems young. If he will hang around for another 2 weeks I will have his "maleness" taken care of. Have already taken him in for tests and shots - first go around. My spade females think it is great to have him here (two cats and a dog) If you have time, thanks, Becky

A: Becky-

There are really only a few times in a cat's life when its age is relatively easy to pinpoint.

The first one is when the permanent incisor teeth come in. This usually happens around 4 months of age. The second time is when the permanent canine teeth (fangs) come in. This usually happens around 6 months of age. For a while after that the teeth are pretty new looking and it is usually OK to assume that the cat is less than a year of age if there is no tartar at all --- but some cats do get older than this and still manage to have great looking teeth.

The next time that it is possible to roughly estimate the age of a cat is when nuclear sclerosis, or clouding of the center of the lens of the eye, occurs. This usually happens in cats around twelve years of age is reasonably consistent if the changes are carefully observed.

That does leave a large gap when age is really anybody's guess. Sorry I can't help you get any closer than this in estimating the new guy's age.

Mike Richards, DVM 6/23/99

Pregnancy, diarrhea and fleas

Q: Hi...I just discovered your pages on the net. I'm new to this kind of thing...computers...but, because my kitty is not feeling well, and I am very broke (a student, and I can't even afford a dr. visit for myself!) I hope you can help me figure out if I really need to take her to the vet.

1. she is a she...about a year old

2. never been pregnant...but may be...(she got out!)

3. is very affectionate...but always has been

4. the weather here has been quite 90's...for a week or so

5. she is drinking water, and eating a little...but eating as much as usual or as much as she did just 3 days ago (the weather has changed)

6. since she may be pregnant, I started giving her a little more milk than I usually do...but not a whole lot...

7. I noticed signs of diarrhea a couple days ago...thought it would pass...and she was eating o.k. then

8. the diarrhea is still with her...and she is a bit listless, not real bad yet, but I do see a difference...

9. I gave her milk this a.m. and usually she likes to lick it up...not soured in her bowl.

10. I do not notice any sign of worm infestation...but she has never been wormed....I gave her her basic vaccinations. (purchased at local pet store)

11. the fleas have just popped out all over. 3 days ago she was almost flea free (she wears a collar, and I comb her daily)...but they are all over now and the house is infested (I have to bomb...but afraid to if she is sick)

12. her breathing seems normal...for a hot day...she may be a little labored...occasionally.

13. the "sparkle" in her eyes seems gone (listless) Could it be the heat? Or pregnancy? Or fleas? I am attempting to feed her a bland diet to see if it helps...she seems "interested" but not too excited to eat.

Thank you so much...yes, you may use my letter or any portion of it in your column. --Mary

A: Mary- Milk will often cause diarrhea. Many cats can not digest the lactose sugars and this leads to intestinal irritation and diarrhea. If this is the cause it usually will respond to with-holding food for 24 hours and stopping the milk. In some cases it is necessary to use an anti-diarrheal medication like Immodium AD (not approved for cats) to control the diarrhea. There are a number of other possible causes, though. Intestinal parasites, bacterial infections, viruses and systemic disorders can all lead to diarrhea. Still, it would be a good idea to stop the milk and see if that helps.

Heat does not generally bother cats as much as dogs but it could contribute to lethargy. Fleas can definitely cause severe enough anemia to produce lethargy and even death. It is important to control the fleas, especially if she is pregnant. She will need all of her blood to support kittens. Program (Rx) is safe to use in pregnant cats but it is slow to control an adult flea problem. Frontline (Rx) would be an efficient adult flea killer and is probably safe during pregnancy but the label does not support that use. If she stays in the house now just treating the house with a good adulticide and a good larvacidal flea product would probably kill the fleas eventually but it would still be slower than treating her. Please consider talking this over with a vet in your area. You will need to see a vet to get the best of the new flea products. That would be a good time to determine if she is pregnant and to get advice on diet and other prenatal concerns. If this is absolutely not possible, at least check out the flea information on our site and get control of the fleas. It could be very important!

Mike Richards, DVM

Bathing Cats

Q: This may seem like a silly question, but what is the efficacy of bathing a cat? I have heard both that you should bathe your cat regularly and that regular bathing is neither necessary nor desirable since cats bathe themselves naturally. We have a black and white domestic short hair cat who has a beautiful coat. However, he has had an unusually large amount of dander lately and his coat has felt oilier than usual (we have been brushing him regularly). Should we bathe him (he HATES it!) or will this just aggravate the problem? Please help! Thank you.

A: E- I think bathing cats can help with dry skin and dander conditions as well as for oily conditions of the haircoat. I would just bathe as often as it seems necessary -- hopefully there will be long intervals between baths! Using a cream rinse is helpful in many instances. I'm not sure if it matters much but it might be worth choosing one for oily hair -- I think they make those. A human one is OK.

Oily haircoats occur with diabetes and hyperthyroidism so it may be worthwhile to have your vet examine your cat, too.

Mike Richards, DVM

Urine odor treatment

Q: Our cats have used a spot in our house to urinate. I believe the problem started when the female had a bout with cystitis. I do not believe we ever completely removed the odor and it is drawing them back to the spot. What would you recommend cleaning the area with? We have cleaned the carpet, replaced the pad and even replaced the wood strips. The female does experience recurring cystitis. It may be that she uses this area only when the cystitis flares up. However I do not understand why she uses the same spot if it is not the odor drawing her back. Any suggestions? Thanks, K.

A: It helps a lot to use an enzymatic type odor remover. There are several of these on the market. Feline Odor Neutralizer (F.O.N.) is a good product for this that we use in our practice. I have seen many recommendations for Equalizer and Nature's Miracle as well. There may be other good ones that I haven't heard of. Removing the odor will usually help a lot. Cats do like to urinate where they have urinated before. It's kind of like finding that gas station with the really nice rest rooms -- you look for it the next time!

Putting a thick plastic wrap or a plastic carpet runner over the spot often helps because most cats don't like to walk on plastic and will avoid it.

It can also help to put the litterpan there and then sloooowwwwlllyy move it to where you want it. Generally you have to move it an inch or so per day at the most, so it really takes a while to get it where you want it to be.

Using one of the cystitis controlling diets can be helpful, too.

Mike Richards, DVM


Q: Dr. Mike, I just noticed that my cat has little yellow things around his anus and I am scared. I had a rabbit once that got maggets and I didn't find them til too late. My cat is completely an inside cat. The thing that scares me is if there is a fly around he will catch it and eat it. I am really not sure what to do. Do you have any suggestions for me? Thanks!

A: You cat probably has tapeworms. Tapeworms release muscular egg packets into the intestine. These egg packets are about 1/2 to 3/4th of an inch long when they first exit the rectum and are capable of movement. They wiggle around, spewing out tapeworm eggs until they use up all their energy stores. Then they dry up and look like rice granules stuck in the hair of the cat.

Tapeworms are carried by fleas and are not uncommon in indoor only cats, due to this. Good flea control will prevent recurrence after your cat is dewormed for the tapeworms he has now. There are safe and effective tapeworm medications available from your veterinarian. They are prescription products so your vet may need to see your cat prior to dispensing them if it has been a while since his last visit.

Mike Richards, DVM

Michal response: Push here and it will take you to a tapeworm picture.

Blood in stool

Q: Dear Dr. Mike, I have a nine month old kitten who has an occasional bloody discharge through his anus. Is this condition serious?

A: It is hard to decide sometimes if small amounts of fresh blood from the rectum mean much in cats. This seems to be an occasional finding in a few cats in which no specific cause can be found. I still think that it is better to at least rule out intestinal parasites and to examine the anal sacs and rectal area for injury. Your vet can check a stool sample for parasites and examine your cat for problems. It is possible (maybe even likely) that your vet will want to rule out other possible problems he or she worries about in this situation.

Mike Richards, DVM

Hairballs in Cats:

Q: Dear Dr. Mike:

I have a balinese cat who is now 1 1/2 years and he has been having problems with fur balls (hacking) for quite sometime. I have been giving him parifin (as suggested by my local vet) and this is not helping. I took him to the vet the other day and she did not want to start testing my cat, as she felt that it was a fur ball problem. His breathing seems to be shallow and gasping like. Do you have any info on this kind of problem. Thank You

A: Now you did it. You forced me to reveal one my quirks as a veterinarian.

I don't believe that hairballs really just occur for no reason and are a problem all by themselves in a cat. At least not very often.

I think that hairballs are a sign of another problem, most of the time. In my area, this is usually a dermatitis problem. Identifying and correcting the underlying problem, like flea allergy, will almost always resolve the hairball problem. When the skin looks normal and I can't find evidence of something like behavioral overgrooming, I suspect inflammatory bowel disease problems. Often, these cats are also vomiting more frequently without hacking up a hairball or they have intermittent diarrhea or soft stools. Their appetite may be irregular. These signs point towards inflammatory bowel disease problems.

So in this case, I fundamentally disagree with the approach your vet is taking. BUT -- your vet is in the vast majority when it comes to how most vets treat hairball problems (or at least most of the ones I know).

So my advice is to push for identifying a cause, even though I know I'm in the minority in that opinion. This is especially true since you feel that there may be a respiratory problem as well.

Mike Richards, DVM

Normal food and water consumption of cats:

Q: Hi Doc: I am mainly interested in knowing how much water and how much food a cat may be expected to consume per unit body weight per day, and how much urine and how much feces a cat may be expected to excrete per unit body weight, assuming moderate conditions of temperature and humidity, moderate activity levels, and good health.

I would also like to get an idea of whether the effect of body weight on consumption is linear, what effect ambient humidity and temperature have, and what effect the proportion of body fat, the activity level, the wake/sleep ratio, etc. have on consumption and excretion rates.

Thanks very much for any informaiton you could supply or any citation you could reference.

A: Nutrition in pets has been studied, extensively in some aspects, but there is a lot yet to learn. This leaves most nutritionists using terms like "generally accepted recommendation" and "most commonly assumed", etc. What this means for the rest of the answer to your question is that some of the information presented is a best guess based on reading several texts, most notably Small Animal Clinical Nutrition III by Lewis, Morris and Hand and Clinical Nutrition in the May 1989 small animal edition of The Clinics of North America.

Cats require approximately 45kcal/lb/day of metabolizable energy (ME). The type of food they eat and the cat's activity level will determine the amount of food necessary to meet this requirement. For a normally active 10 lbs. cat, hunting mice on its own, this is about 10 mice a day. For a 10lb. cat eating cat food, this is about 1 cup of dry food or 10oz of canned food a day. Cats vary widely in their food requirements, though. The best guideline is to judge each cat's needs individually. Feed them enough to maintain their ideal body weight but not more than that. The relationship between size of the cat and dietary needs is not exactly linear. A small cat (6 lbs.) would require about 3/4th of a cup of food, while a big cat (12 lbs.) only requires slightly more than one cup -- about a tablespoon more, again assuming "normal" activity and health. I was not able to find any references to stool volume excreted. This would vary according to the digestibility of the food. One of the selling points of premium diets has always been lower stool production.

Cats are thought to consume between 20 and 30ml/lb/day of water. Using this formula, a 10 lbs. cat will drink 200 to 300cc of water or about a cup of water a day. A cup is about 250cc of water.

This too can vary widely. Urine output closely matches water intake, usually running between 22 and 30ml/kg/day.

Activity levels have a great effect on dietary needs. I am pretty sure that this is probably also true of ambient temperature and other factors.

Hope this helps

Mike Richards, DVM

Litterpan or Elimination Behavior Problems

Litterpan problems are very common in cats. It helps to think about this problem from the cat's point of view sometimes when trying to deal with it. Cats like to have a clean, inviting place to defecate and urinate. Remember some of the dirty bathrooms you have had to decide whether to use or not, and you can relate to this feeling. So it is very important to make the litterpan as attractive as possible for use.

Keep it very clean. Use a litter that the cat likes. The clumping type litters are the most commonly preferred litters in surveys of cat preference. If you are not using this type and your cat has a problem, it can help to switch.

The litterpan should be in a convenient, but private or at least semi-private site. It helps very much to have one more litterpan than you have cats. In multicat households where this is impractical, it can help to give the problem cat access to the litterpan, alone, for several minutes twice a day.

When a cat is using a place in the house other than the litterpan to urinate or defecate, the opposite is also true. You want to make these spots unattractive. Cleaning the area with an enzymatic cleaner so the cat is not drawn back to the same site helps. Putting plastic or aluminum foil over the area, if possible, can be very helpful. Putting the litterpan at the site the cat prefers, then very gradually moving it to a site you like can be helpful.

Cats may not be using the litterpan because they are ill. Cystitis (a bladder infection or inflammation) is a common problem that can lead to litterpan aversion. One theory is that the cat associates the litterpan with the painful sensation or urinating with this disease and avoids it. Some anatomical defects can lead to an increased need to urinate frequently. Diseases that increase the need to urinate, like diabetes and hyperthyroidism should be ruled out if that seems appropriate. Disorders that might affect a cat's ability to get to the litterpan, like low potassium levels in the bloodstream or arthritis need to be considered. If there are no medical problems and good litterpan maintenance is in place, then the problem may be behavioral for othe reasons. Some cats are not using the litterpan because they are marking territory. This can occur in either male or female cats. It is more common in cats in multi-cat households, especially if there are five or more cats. It can occur when an inside cat is bothered by frequent appearances of an outside cat at the windows. In this case, limiting access to seeing the other cat can help. Urine marking behavior is often responsive to medical therapy with medications like diazepam (Valium) or buspirone (Buspar). It can be responsive to megestrol acetate (Ovaban), but this medication has significant side effects that must be considered. It should be a last resort medication. If a cat is not neutered this is often helpful, even after urine marking (spraying) behavior is established.

Mike Richards, DVM

Last edited 09/17/02


Michael Richards, D.V.M. co-owns a small animal general veterinary practice in rural tidewater Virginia. Dr. Richards graduated from Iowa State University's College of Veterinary Medicine in 1979, and has been in private practice ever since. Dr. Richards has been the director of the PetCare Forum...