DEAR DR. FOX: We have an 18-month-old German shepherd/Lab/Akita mix who we adopted from the Humane Society at 5 months old. She is very smart, and I have trained her in good manners and many tricks at our house. My main problem is that she acts aggressive and hostile when she cannot get to another dog when on a leash.

She is fine at the dog park and has playdates with a neighbor's dog. However, when she is on the leash and sees another dog within 40 to 50 feet, she becomes almost unmanageable. She growls, snarls, lunges and acts like she wants to kill the other dog. Once the other person lets me come over and after sniffing the other dog, my dog is fine and we can walk together.

I have used the clicker for training and used lots of treats on walks, but she ignores me when she sees another dog. I am at my wit's end and do not know how to stop this behavior. Can you help me? -- S.Z.-D., St. Louis

DEAR S.Z.-D.: Your letter is important for many dog owners to understand why their pets behave as yours does when on the leash and being approached by another dog.

First, understand that a dog who is leashed feels restrained and, therefore, vulnerable. Excitement and pulling on the leash means you pull and jerk her collar, which acts as an inciting, if confusing, signal to her. So stay calm, because your emotional reactions are transmitted to your dog through the leash. Try fitting her with a harness around her chest, either alone or coupled with an over-the-muzzle halter, similar to those used to effectively and painlessly control horses.

Be patient and keep the faith -- she is still young and excitable, and she will calm down in a few months when she matures, around 2 1/2 to 3 years old. Never scold or yell. Just stand very still and let her pull and do whatever while you have your feet firmly planted. On walks, teach her to sit and stay with intermittent rewards of treats. Give her those commands when you see a dog coming. She may eventually make the connection and be still, but right now her brain is lacking in self-control/internal inhibition, which she will hopefully acquire with maturity.

DEAR DR. FOX: We read your column in the Fargo, N.D., Forum. Recently, you requested feedback on pet improvement after changing pet food.

Our cat is a female American shorthair, 11 years old, spayed and indoor-only. Her original food was Hills Science Diet Active Longevity. She was overweight at 14 pounds. For about a year, she had a cyst on her cheek that was the size of a large grape, which we had drained by the vet. It did not seem to bother her. She had bowel troubles from time to time, a dirty rear end and anal gland problems. She would chew at her fur a lot.

About five months ago, we switched her to Wellness Indoor Health Dry Food and Wellness Indulgence Poultry Packets (wet food). She quickly took to the new diet. As of now, the bowel and rear end problems have cleared up. She has lost 2 pounds. She is much more lively, alert and active. The cyst has shrunk considerably and seems to be drying up. She leaves her fur alone also.

Thanks so much for the information. -- E. & C.V., Torrance, Calif.

Dear E. & C.V.: Thanks for confirming the benefits that can come when one focuses not simply on the symptoms when an animal has health issues, but on what the animal is being fed. Some ingredients in many popular and widely advertised brands, especially corn and other genetically modified ingredients (GMOs), may be putting our animals at risk -- even foods sold by the vet. All pet and human foods should be labeled to indicate if they contain GMOs. It's best to buy USDA organically certified produce and cook from scratch using known ingredients. For an in-depth review of what goes into many pet foods, and for home-prepared recipes for dogs and cats, see the new paperback edition of the book that I co-authored with two other veterinarians, "Not Fit for a Dog."

(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 DrFoxVet.com.)

DEAR DR. FOX: I was disappointed in your recent response to G.L. in Washington, D.C., the feral cat colony caretaker. Instead of providing him with a link to Alley Cat Allies (alleycat.org), a nonprofit group dedicated to helping cats, you persisted in providing antiquated arguments for the death of cats. The website has an entire section that would have answered G.L.'s questions much better than you did, which was to advocate he euthanize his cats.

You also maintain that cats kill birds and other wildlife. My feral cat takes out the moles that destroy my yard, kills copperhead snakes and keeps down the mouse and other rodent population. Take out the cats through your plan, and these creatures have no natural predator and their populations explode.

I would suggest you educate yourself before giving the public outdated information. You have lost credibility with me for perpetuating stereotypes. I hope you can inform the public in a future column that there are better ways and better answers than what you wrote. -- M.D., Labadie, Mo.

DEAR M.D.: While I appreciate what Alley Cat Allies is doing to help increase public awareness about the plight of free-roaming lost and feral cats, I am not alone in my opinion. Many in the veterinary profession, as well as other wildlife biologists, question the wisdom and humaneness of TNR (trap-neuter-release) and people maintaining colonies of feral cats. Your statement that I advocate only euthanasia is incorrect.

By your own admission, your cats are killing wildlife. The moles are part of the natural environment you occupy, and I, for one, welcome them. They were here on Earth long before we humans became an infestation, and in many cases, they benefit the soil. Copperheads and other snakes are natural rodent controllers, which helps control the viruses rodents transmit, such as the hantavirus.

According to the American Bird Conservancy, only about one-third of the 77 million pet cats in the U.S. are kept indoors exclusively, while free-roaming cats kill an estimated 500 million birds annually -- a staggering figure. Fledglings who have just left the nest are especially vulnerable to these domestic and feral predators.

Domestic cats have no place outdoors, and our compassion for these homeless animals should not trump common sense and sound science.

My home is enriched by two feral cats my wife and I trapped and saved from Minnesota winters. One took six months to venture out from a safe corner he chose as his refuge. Neither shows any desire to go back outdoors, and both are now wonderful companions who I can kiss on their tummies and play wild games with at night. Trap-neuter-rehabilitate is my TNR mantra, with release through euthanasia being the very last option.

DEAR DR. FOX: We, too, have taken in outdoor cats (more or less feral) who, once given the opportunity to be indoor cats, never wanted to run wild again. For years, my wife and I had a brother and sister from the same litter, Oberon and Titania, who had been outdoor cats for the first six years of their lives. (My wife fed them, but we didn't have the opportunity to take them in at first.) Once our situation changed and we brought them inside, they would frequently sit by the sliding-glass door and watch the outside for hours on end. If the front door was left open, they might slip outside just for a sniff, but they never left the front steps, and if the door closed behind them, they'd immediately scratch at it and meow to be let back in.

We now have a little cat, Oliver, who was found as the neighborhood stray when he was not quite fully grown. He, too, loves to sit on the window ledge and watch the outdoors, and if the door is opened, he gets excited and will investigate, but if it's held open for him he will rarely venture out. If he does, he never goes more than a few feet from the door. I think all three of these cats remembered what it was like to be an outdoor cat and had no desire to revisit that cold, wet, lonely experience. -- J.Y., St. Louis

DEAR J.Y.: Thanks for confirming just how sensible cats are when it comes to knowing life indoors is better than having to fend for themselves outdoors! Some people forget their ancestors came from the deserts of North Africa.

As I have shared with readers, our two formerly feral cats never want to go outdoors, but one of them loves to watch the creatures around our bird feeders through the screen door and from various window ledges. It's his TV!

Making provision for indoor cats to look out from an extended, carpeted window ledge or cat condo placed beside the window, ideally with a bird feeder outside in full view, is the kind of environmental enrichment most cats really enjoy.

(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 DrFoxVet.com.)

DEAR DR. FOX: Do you have a remedy for curing/eliminating ear mites? Does witch hazel work? Is it safe for dogs? -- P.R., Duluth, Minn.

DEAR P.R.: This mite, otodectes cynotis, is passed from animal to animal by direct contact. Often there is a cat in the home with no evident symptoms, and a dog in the same home gets the mites in the ears and scratches and shakes in obvious distress. These mites can infest the face and other parts of the body, but are most often confined to the external ear canals. They cause a dark brown or black tarry secretion.

The best treatment is with an insecticide such as ivermectin drops or pyrethrin. I would not use herbal products because effectiveness may not be as good as with insecticidal drugs, especially when there is much suffering to the infested dog. For best results, the ears must be thoroughly cleaned before applying medication. Repeated treatment after seven to 10 days is advisable. Witch hazel is a soothing herb for many skin and ear issues, but it will have no significant impact on the offending mites.

DRIVING SAFELY WITH YOUR DOG OR CAT

New Jersey dogs and cats will have to be buckled up for safety just like humans if legislation proposed by Assemblywoman Grace Spencer (D-Essex) is passed. I fully endorse this kind of initiative, with punitive consequences for violators, for every state to adopt.

Pickup truck drivers with loose dogs in the back are my personal abomination, along with drivers whose use of cellphones and other hand-held electronic devices put us all at risk.

Unsecured dogs in the back of pickup trucks, or tied so that they could fall out and hang themselves, are part and parcel of our blighted rural landscape that should, along with puppy mills and dog and cock fighting, be outlawed, with punitive consequences for those who flout the law. Mitt Romney, who tied his dog in a crate to the roof of his car, should be no exception.

A barrier between driver and the animal, who is free to move around in the rear section of the vehicle, is acceptable, provided the animal wears a collar with ID in case of accident. Police officers often shoot larger dogs defending the vehicle after an accident if they are not easily restrained or contained. Few cats and dogs will take to restraining straps and tethers, so I advise crates or cages, even for short journeys.

In Arizona and Connecticut, drivers may be cited for distracted driving if an unleashed pet interferes, and pets are banned from operators' laps in Hawaii. But if Spencer's bill passes, New Jersey will be the first state to mandate pet restraints, according to the American Automobile Association.

Opposing New Jersey Republican Assemblyman Jay Webber has introduced his own bill that says failure to restrain an animal isn't inhumane. That is not the issue, and as a veterinarian and animal behaviorist, I can affirm that restraining an animal can be inhumane. Some form of humane containment/restraint for dogs and cats, for their safety and for the safety of other passengers, is called for when they are being transported by road, air or sea.

Just like children, many dogs will initially fight and chew on safety harnesses in the car, but with patience and reward treats, they will soon habituate and enjoy the ride. Failure to properly restrain any animal during transportation should be regarded as a gross misdemeanor, certainly not as an inhumane, deliberate act of abuse/cruelty, but as an act of ignorance or indifference, for which there is no defense because of the legitimate potential for possibly harmful consequences to the animals and to the people in the vehicle with them.

I also urge drivers to be mindful in hot weather -- leaving a dog in the car for even a few minutes could be fatal. Never drive with your dog's head out the window because of potential eye and head injury and even death when windows are accidentally closed, crushing the neck, or opened so the dog falls out.

(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 DrFoxVet.com.)