DEAR DR. FOX: Two years ago, I adopted a beautiful male snowshoe cat from the animal shelter. He is very sweet, natural and content to be with me. But in all this time, I have never heard or felt him purr. I've had cats my entire life, and I have never known one not to be able to purr.

Do you have any explanation for this? He's 4 years old. -- P.G., Virginia Beach, Va.

DEAR P.G.: There is no scientific answer to your question, only educated guesses about genetics and individual differences. Many readers will attest to the fact that their cats never purr or meow. Some silent cats become vocal after a vocal cat in the home passes on.

Fear is a significant inhibitor of purring. The word "copycat" is appropriate -- cats learn from one another, so being separated from other cats at a young age might account for some cats' vocal sounds not being triggered.

Try brushing your cat, and learn some massage therapy to help induce deep relaxation, which I've detailed in my book, "The Healing Touch for Cats." Hearing harp music or Gregorian chants can make cats relax and might get yours into a purring mood.

While cats may purr to relax and convey friendly intentions, one scientific theory holds that the vocal vibrations may influence bone density and help prevent osteoporosis. My view is that since purring may involve circular breathing to create an almost-continuous sound -- a trick some musicians employ, as I do when playing a didgeridoo -- the cats may be inducing a meditative or altered state of consciousness.

DEAR DR. FOX: We adopted a wonderful 2-year-old shelter dog last summer, but he has one bad habit we need your advice on: He eats his stool. We've been told it's not uncommon, won't harm him and he'll probably outgrow it.

But the problem is worse because we have three other dogs, and he wants theirs too. Our vet gave us For-Bid to add to all the dogs' food, but it didn't work. We tried Stool-No! tablets, pepper on the piles and scolding and shaking coins in a can when we catch him in the act. We have to go into the yard with him and follow him around now.

Out in the cold last night, walking around with our flashlight, we started wondering what Dr. Fox would do. Since it's not harmful, should we just relax, let him out unsupervised and try to not think about what is happening?

We walk our dogs every morning until they go, and we pick that up, but the rest of the time requires watching him closely. We used to be able to let our dogs in and out whenever they wanted.

Also, he poops about four times a day, which seems high. Is there a food or diet you recommend that might help with that? -- B.B., St. Louis

DEAR B.B.: I receive many letters from dog owners who, like you, have a stool-eating (coprophagic) dog. Go to my website, www.twobitdog.com/DrFox, and check the archives for various answers and solutions to treating this problem.

This obnoxious activity has psychological and physical causes. The former is linked with dogs being caged or crated for long periods of time and, out of boredom or desire to keep their "den" clean, they engage in coprophagy. The habit can persist even after dogs are provided normal living spaces and outdoor activity -- which may be why he cleans up the other dogs' poop. Try using a muzzle when he's out in the yard with your other dogs; it may break his habit after a few weeks.

Possible physical reasons include dietary or digestive issues. Many dogs show improvement when given brewer's yeast (1 teaspoon per 30 pounds of body weight) in their food, plus 1 tablespoon of probiotic-rich yogurt or kefir. Many dog foods are high in cereals and fiber, which can mean large-volume feces and frequent evacuations, so you may want to transition all your dogs to canned food or low-fiber dry food -- or you can try my home-prepared recipe.

(Send all mail to animaldocfox@gmail.com or to Dr. Michael Fox in care of Universal Uclick, 1130 Walnut St., Kansas City, MO 64106. The volume of mail received prohibits personal replies, but questions and comments of general interest will be discussed in future columns.

Visit Dr. Fox's website at www.twobitdog.com/DrFox.)

DEAR DR. FOX: I have a 5-year-old pug. He has several black spots that look like warts on his stomach.

The veterinarian I took him to retired, so a young vet has taken over. The previous vet put him on steroids, but the new vet said she could remove them with surgery. She tells me the warts are caused by a virus.

What could be causing these growths? What options do I have besides surgery? Can I be infected by this virus? -- D.J.W., Uniontown, Pa.

DEAR D.J.W.: Yes, your dog's warts are caused by a virus. But since it's different from the viruses that cause warts in humans, you have nothing to worry about. You can't get an infection from handling your dog.

I am glad that the veterinarian who prescribed steroids has been replaced. Steroids could make the problem worse and have other side effects.

Try "painting" the warts two to three times a day with apple cider vinegar -- you'll have to stop your dog from licking it off for about 30 minutes. If you see no improvement in a few weeks, I would consider surgery. Have the surgery done soon if any of the warts seem infected or ulcerated and are causing your dog discomfort.

Several other home remedies for warts are in the archives section on my website, www.twobitdog.com/DrFox. Some readers have found success by applying vitamin E squeezed out of the gelatin capsules.

DEAR DR. FOX: My ferret, Sparky, is 6 years old, and he has halitosis. When I am playing with him, my hands sometimes smell bad from his saliva. Sometimes he drools a lot.

He won't chew bones to keep his teeth clean. What do you advise? -- S.K.L., Springfield, Mo.

DEAR S.K.L.: Ferrets, especially older ones like yours, are prone to developing gingivitis, an inflammation and infection of the gums; tartar, especially on the upper back teeth; and periodontal disease.

Have your ferret examined by a veterinarian, especially because any of these dental problems can lead to complications, including heart, kidney and pancreatic diseases due to bacteria, toxins and inflammatory substances that build up in the ferret's diseased oral cavity.

After professional dental care, maintain oral hygiene by providing your ferret with thin strips of raw beef or slices of raw turkey gizzard to chew. Applying PetzLife Oral Care gel or spray will help keep the teeth free of tartar and maintain healthy gums.

DEAR DR. FOX: I had a cat named Samantha who lived to be 22 years old. The vet said he could have lived until he was 23 years old. (He had only nine months to go.) I had to have him put to sleep as he had throat cancer. The vet said he lived a good life and was well taken care of.

He ate all types of dry and moist cat food, plus tuna, chicken, turkey, salmon, ham, sweet potatoes and flaxseed oil. He was an indoor cat who never got fleas and who walked on a leash like a puppy. He was more like a kid than a cat.

He slept in my arms like a baby at night. He would use his litter box one time, then come to me and meow to let me know he wanted the litter changed. When company would come, he would go down the steps to greet them. (I live in an upstairs apartment.) He loved to go for walks, and he loved to have his hair combed like a person.

I could write more, but I should stop. I'm thinking about writing a book about that cat. -- N.K., Romney, W.Va.

DEAR N.K.: Cat owners and lovers will enjoy your brief story about life with Samantha.

Some of the ways to help cats enjoy a long and healthy life are confirmed in your letter -- love and understanding, a nutritious diet, and keeping your cat indoors unless walking on a leash.

Flaxseed oil is good for dogs and most humans, but it is inadequate for cats, who need fish oil as a source of essential fatty acids.

My book "Supercat" details other ways to enrich the lives of indoor cats and includes interactive games that can be applied to test cats' IQs. Some cats are brighter than others; they have greater insight, reasoning, focus and dexterity.

I wish more people would have more than one cat. Adopting littermates or a mother and her kitten(s) is an easy way to have multiple cats. Check my website for details about introducing a new cat.

(Send all mail to animaldocfox@gmail.com or to Dr. Michael Fox in care of Universal Uclick, 1130 Walnut St., Kansas City, MO 64106. The volume of mail received prohibits personal replies, but questions and comments of general interest will be discussed in future columns.

Visit Dr. Fox's website at www.twobitdog.com/DrFox.)

DEAR DR. FOX: My daughter found Mulligan the kitten on a golf course in Richmond, Va. Mulligan had partial paralysis in her hind legs, but quickly regained use of them. She had extreme difficulty with bowel movements, probably as a result of the same injury that created the partial paralysis in her legs. No amount of Cat Lax, the natural laxative, helped.

About two months after we got her, she developed a prolapsed rectum from straining to defecate. After an emergency visit to our vet to repair the damage and take X-rays, we took her to a specialist at an animal hospital. The doctor confirmed that she had a megacolon, and surgery was performed that day to remove all but an inch and a half of her colon.

The vet prescribed mixing Metamucil with her food to provide near-normal bowel movements. For 15 years, we did this with generally successful results. Mulligan ate a 5.5-ounce can of wet food each day, and although she struggled at times in the litter box, she was able to lead a fairly normal life as an indoor cat. She was a joy to my wife, who took care of her for all those years. -- J.B., Potomac, Md.

DEAR J.B.: Thank you for sharing the encouraging success story about your injured cat who, after appropriate diagnosis and treatment, enjoyed a long and happy life.

Many people in your situation would have elected to have the cat euthanized. Costs notwithstanding, and with never a guarantee of total recovery, cats and dogs have amazing recuperative abilities when coupled with the expertise of a veterinarian. Above all, animals need the commitment and patient support of their in-home caregivers, without whom the possibility of even partial recovery may never become a reality.

DEAR DR. FOX: I have never told this to anyone before, but I think it may help some readers.

I had a cat who slept and died at the foot of my bed. About a year later, when I went to bed at night, I felt it walking around at the foot of the bed. I had a dog who would jump up and run next to my head, trembling, when it happened. Eventually the dog refused to sleep on the bed. It scared me so much I would say the Lord's Prayer, and the walking would stop.

I miss the cat and dog so much. The little dog died from kidney failure at about 4 years of age. The cat was an indoor-outdoor, and someone poisoned it. It dragged itself home after it had been missing for two days. I laid it on my bed. It had a few seizures, lifted its tail up and down as if in farewell and died.

The walking was a constant foot padding I felt on my feet and lower legs. I'm glad it stopped. -- T.L., Chesapeake, Va.

DEAR T.L.: Some people with experiences such as yours think they are going crazy, or share your fear over some disembodied presence that they can feel but not see. Such presences can affect senses other than touch -- some people hear the claws on the floor, purring or whimpering, or see a visual image, often fleeting or mist-like. For details, visit my website, www.twobitdog.com/DrFox.

The logical argument that all of these manifestations are like holographic projections of our own conditioned memories is defeated when other household members -- human and, in your case, a companion animal -- also sense and respond to the disembodied presence.

Apart from your cat's traumatic and tragic death, your experience, if not an affirmation of your cat's devotion and attachment to being close to you on the bed, is at least a phenomenal one that was affirmed by your dog. And it opens us to the great mystery of life and spirit, if not to feelings of reverence and awe.

(Send all mail to animaldocfox@gmail.com or to Dr. Michael Fox in care of Universal Uclick, 1130 Walnut St., Kansas City, MO 64106. The volume of mail received prohibits personal replies, but questions and comments of general interest will be discussed in future columns.

Visit Dr. Fox's website at www.twobitdog.com/DrFox.)