Dear Dr. Fox:

Jacob, our 3-year-old fixed male cockapoo (he may also have some terrier in him), has "visitors leaving" anxiety.

It started about a year ago with Jacob jumping and nipping on the sleeves and feet of our weekly housekeeper as she left for the night. Once the behavior began, Jacob repeated it with all departing visitors. To protect them, we now put the leash on Jacob whenever we are able to plan for a visitor's departure. Even with the leash on, though, every time a visitor gets up to leave and approaches the front door, Jacob violently pulls on the leash, manically scratches the floor and barks violently.

During the six-month period following the initial onset of this behavior, Jacob was twice attacked by a neighbor's pit bull/chow mix; perhaps this added a level of anxiety. In fact, he restarted the behavior following a very difficult recovery from the second, more serious attack by the dog.

He never exhibits this behavior when the three of us leave the house (including our 12-year-old son), and sometimes does not exhibit this behavior when close friends (who twice dog-sat for us) leave.

A vet behaviorist recommended a behavior modification program, but it was impossible to implement because it required visitors to come often and devote a lot of time to helping Jacob. We are hoping you can offer a workable, non-pharmaceutical treatment option.

L.R., Silver Spring

Your dog is indeed suffering from an anxiety disorder that could well have been aggravated by being attacked by your neighbor's dog,

The best and most workable behavior modification program is to hire an animal behavior consultant who know the ropes and will put your dog through a desensitization and re-motivation program. But you can try this procedure first:

Get a dog-training clicker or whistle (or shake a coffee can containing coins and pebbles) and employ it as soon as your dog begins to act up -- as your housekeeper is leaving, for instance. The noise will break his focused obsession. Keep him on the leash and, immediately after the noise distraction, give him a treat or favorite toy to re-motivate him. Have your housekeeper come and go several times and repeat the noise-reward sequence, then praise him for being still.

Dear Dr. Fox:

Our 15-year-old cat gets regular vet care and is in good health, but in the last two months she has developed a new behavior.

She goes up the steps to the second floor. When she gets there, she stops and spends about 60 seconds calling out very loudly and in the most prolonged, mournful tones imaginable, as if to say, "See what a tragic life I have!" Then she is back to normal. What gives?

J.D.H., Washington

To be on the safe side, have your old cat checked over by a veterinarian. Yowling could mean she has physical pain and therefore a medical problem. But, most likely, the cause is psychological.

Some cats yowl, especially in the evening, when they want to go outdoors -- it's the "call of the wild," if you wish. In older cats like yours, it may be associated with senile dementia, deterioration of the senses (especially sight and hearing) that makes the animals experiencing it anxious. In that case, interrupt her yowling and offer her the comfort and security of your arms.

Dear Dr. Fox:

I have a 14-year-old cat who went through a four-hour surgery years ago for a crushed hip.

When her arthritis became bad I gave her medication, which helped, but as I became older I hadn't the strength to get the pills down. She became much worse.

Every day I put colloidal silver in my drinking water for my arthritis and allergies. I started adding some to my cat's water. It is tasteless. She improved almost immediately. She is now like a much younger cat.

This can be purchased (expensively) or you can make your own for the price of a small kit and some water. I'm a firm believer in this treatment. Our whole family takes it now.

S.H., El Campo, Tex.

Good to hear about your success using colloidal silver, which provided such dramatic relief for you and your arthritic cat. I would like to hear from others, especially veterinarians, who have used colloidal silver for this and other conditions.

Great caution is called for, however, since this compound can cause kidney damage. I am all for finding cheap, safe and effective alternative medicines, but clinical studies are called for, and over-the-counter purchase of such products for home use without consultation with a holistic human or veterinary doctor is to be avoided.

Michael Fox, author of many books on animal care, welfare and rights, is a veterinarian with doctoral degrees in medicine and animal behavior. Write to him in care of United Feature Syndicate, 200 Madison Ave., New York, N.Y. 10016. The volume of mail received prohibits personal replies, but questions and comments of general interest will be discussed in future columns.

(c) 2004, United Feature Syndicate Inc.