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A steady diet of fish can cause health problems in cats

Dear Dr. Fox: Some time ago, I came home with some sushi, and my 6-year-old Siamese cat, Suzi, went crazy for it. I now give her treats of raw fish every day, and sometimes thawed fish fingers. Is that healthy for cats?

K.M.W., Potomac, Md.

DF: My answer is an emphatic NO! Most fish — and some more than others, especially white fish and herring — contain enzymes called thiaminases. They destroy thiamine, an essential B vitamin.

Cooking the fish destroys both the enzymes and much of the thiamine, dietary deficiencies of which can result in gastrointestinal, neurological and other health problems.

So a diet primarily of fish, cooked or raw, is not good for cats. They are, after all, originally a desert-dwelling species.

To learn about feline nutrition and the hazards of many manufactured cat foods, check out the book that I wrote with two other veterinarians, “Not Fit for a Dog: The Truth About Manufactured Cat & Dog Food.”

There are ethical reasons to reduce our consumption of seafood. For details, go to


Dear Dr. Fox:Our healthy 12-year-old domestic shorthair cat started limping about four months ago. The problem seemed to be one of her hind legs.

I took her to her vet, who could not elicit any joint pain or tenderness. Molly wouldn’t walk for the vet out of fear — she crouches and shakes during vet visits — so he never saw her limping. He asked me to get a video of her limping on my smartphone and show it to him.

Molly’s limp went away a day or two after the visit, and I was unable to capture it on film. I was surprised when Molly’s vet said that cats rarely, if ever, get arthritis. It seemed that her limp was more pronounced after she had been sitting, and the hind leg seemed to feel a little better after she moved around.

The limp has returned, and I have captured it on film and will take it to the vet. What could cause on-again, off-again leg and hip tenderness if not arthritis? Molly is an indoor cat.

B.L., Chesterfield, Mo.

DF: Cats are notoriously difficult to examine in the veterinary clinic setting when they are tense and afraid. Pain symptoms are masked, and palpation is difficult to perform when muscles and limbs are tensed.

Any veterinarian who says that degenerative joint disease and arthritis is rare in cats needs to have a refresher course in feline medicine and nutrition.

See my book “The Healing Touch For Cats” to learn about the benefits of massage therapy for this common condition in older cats. I advise beneficial supplements, especially good-quality fish oils or omega-3 supplements from algae if the cat does not like the fish oil source of these essential fatty acids, which are anti-inflammatory and help with arthritis and other conditions.


Dear Dr. Fox:My friend Dara rescued an elderly, medium-size female dog, Josephine, from life on a short chain in a back yard. It took years for the “owners” to agree to surrender the dog, and only because the dog had become ill and would have died during the recent cold spells.

Josephine is still shy and reluctant in her new home, which she shares with Dara, her husband and two male dogs. Josephine has taken ownership of the doggy door and will growl at the other dogs when they want to go outside. To my knowledge, she has not nipped anyone, but her growl is intimidating enough to stress out the other dogs.

What do you suggest? Josephine is still shell-shocked from her 10 years on a chain. Dara wants her to feel loved and accepted but she cannot tolerate Josephine being the gatekeeper to the potty.

H.S., St. Louis

DF: Dogs with post-traumatic stress disorder need great sensitivity applied to any behavioral correction or modification.

It is good that she is beginning to assert herself with the resident male dogs, up to a point. But if they are showing signs of anxiety, then some behavioral redirection is needed.

If she is not freaked out by the sound of a training clicker I would train her to come for a treat every time she hears it. Alternatively, you can use a squeaky toy. Squeak it, and the reward is for her to chase it.

This conditioning will have to be done with the other dogs in another room. Food reward rather than a squeaky toy reward might set up some rivalry between the dogs, so the choice of behavioral modification will have to be determined through trial and selection.

Alternatively, train the new dog to sit and stay on command, while on a leash. Give her a reward when she obeys. With her on the leash, close to the dog door, give the sit and stay commands when the other dogs want to go out. If she snarls at them, repeat the sit and stay commands. Coupling the verbal command with a raised then slowly lowered hand facilitates the learning process.

If these measures fail, I would set up a low, 4- to 5-foot-long railing on the door frame so that the dogs wanting to go out have some protection from her. I hope these ideas help.


Dear Dr. Fox:My 11-year-old Havanese dog is suffering from tartar-encrusted teeth. Her front teeth, top and bottom, have become loose and are beginning to fall out.

At times, she is unable to eat her dry food. Her breath is terrible. I am desperate to find a solution and end her discomfort.

M.C., Raleigh, N.C.

DF: When a dog or cat reaches the stage of having difficulty eating because of dental calculi, scale, tartar and associated halitosis, you know that you have a serious health issue to address without delay. It’s likely that one or more rotting teeth must be removed. There might also be infection and inflammation of the gums (periodontal disease), which can spread via blood circulation and damage the heart, kidneys and other internal organs and also infect the jawbone.

I wonder why no veterinarian gave you advice on canine oral hygiene and preventive dental care. Perhaps your dog has not had a checkup for some years. Either way, a full veterinary examination is called for immediately.

Before your dog is subjected to oral surgery, the veterinarian should advise you of the risks, including that of giving a general anesthetic. This is needed for extractions, but many veterinarians avoid it when minor tooth scaling and cleaning are needed. Oral antibiotics are often prescribed for human, canine and feline patients before major dental work.

I would also recommend using PetzLife oral care products for five to seven days before any dental work. These gels and sprays applied to the teeth and gums can reduce infection and inflammation, thus reducing possible complications associated with oral surgery and general anesthesia. PetzLife offers natural, herbal ingredient formulations for oral health maintenance along with safe chew toys and crunchy treats. Go to for details.

Michael W. Fox, author of a newsletter and books on animal care, welfare and rights, is a veterinarian with doctoral degrees in medicine and animal behavior. Write to him at United Feature Syndicate, 1130 Walnut St., Kansas City, Mo. 64106.

2014 United Feature Syndicate


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