Dr. Deb: The Ugly Side of Dogs

As many of you know, dogs are some of my most beloved friends and companions. This past month, however, I’ve seen their dark side.

I became embroiled in a “dangerous dog” case. It involves an unneutered male of a breed known for being independent and possibly having aggressive tendencies. This particular dog has become increasingly aggressive over time. He’s unlicensed, never has a collar on, and is never confined. Despite living on a fairly busy street, he’s managed to successfully dodge cars. He’s been seen roaming as far away as 10 miles from home.

While running loose (now, with another dog as a partner) this fall, he became even more of a nuisance. He’s been eliminating on people’s houses, defecating on their steps, threatening their dogs and starting to harass livestock.

People spoke to the owners about the need to confine this dog and the tragedies that could result. Obviously they didn’t care. Early one Tuesday morning, this dog became a suspect in the killing and wounding of a group of ducks. These ducks were used by dogs for herding training. The hapless ducks probably didn’t even panic at first, since they were used to being around friendly dogs. Those ducks who survived this attack may never work again.

The dog wasn’t caught then, but numerous people saw him. The owner said his dog had not been outside. According to the law in many states, dogs harassing or killing livestock can be shot on sight.

Later that same day, even while the dog control officer was taking a statement from the owner, the dog in question returned to the place where the ducks had been killed and attempted to get into the sheep’s pen. Fortunately, he was spotted before he could get in and was chased off. But he threatened, growled, and bared his teeth at the adult human who chased him off.

It was obvious that this dog had simply returned to kill again, as such dogs will. The owner agreed to take the dog to the humane society.

But the man did not take his dog to the shelter. He gave him away, instead! This dog will return and he will kill again. (He’s never in his life been confined and has roamed widely, as already mentioned.) It turns out he was already a suspect in the killing of a deer.

As I type, this dog’s rabies status is unknown. His owner won’t reveal his whereabouts, so we had to involve a sheriff and a judge. There was a hearing, where it became known that the dog had, months earlier, bitten a young boy in the face. This resulted in a trip to the emergency room for the child, where he was sutured. The boy will, obviously, have a scar. Unfortunately, the chain of communications between the hospital and public health officials broke somewhere down the line. Otherwise this dog would probably have been removed as a threat after the attack on the boy.

Is this a bad dog? Probably not. In the right hands — neutered and raised with care, training and socialization, he might have been a terrific dog. A very experienced, conscientious owner might have been able to steer him in the right direction. But now the dog awaits a decision on his fate: euthanasia or lifetime confinement in a secure, fenced enclosure.

The dog clearly shows a link (at least in his case) between aggression toward other animals and aggression towards people. Many dogs are aggressive towards other dogs, but wonderful with people. But this dog crossed the line. He represents a classic case of all that can go wrong in the partnership of man and dog.

After almost five full weeks, this case was finally resolved. The owner didn’t want to confine his dog (I have to admit, it would have been a rough life for a dog accustomed to running free), and agreed to have the dog euthanized.

Please train, neuter and confine your dogs. Any dog can get loose a few times by accident, but an untrained dog who runs loose all the time is a disaster waiting to happen. In addition, many states or municipalities have leash laws and regulate where a dog can run free.

Many dog attacks could be prevented with the simple use of a leash. Each time a dog runs loose and damages property, or frightens or harms people or other animals is another justification for the people who want to strictly regulate or even eliminate pets. Be a responsible pet owner so that you can be a pet owner!

Bladder Cancer

Cancer is a frightening word that conjures up images of weakness, nausea, hair loss, and death. In reality, cancer is a disease process where a cell continually divides and makes new cells, and doesn’t respond to the body’s normal signals to slow or stop its division. In benign tumors, the abnormal cells accumulate in one region and form a mass that doesn’t spread to distant areas. Malignant tumors (cancer), on the other hand, invade the tissues where they originate and ultimately spread by a process called metastasis.

Dogs can develop many different kinds of tumors. Usually, cancer occurs in middle-aged to older dogs, but certain types of cancer also occur in younger dogs. Cancer of the urinary bladder occurs in dogs and cats. Transitional cell carcinoma is the most common tumor of the urinary tract in dogs, and tends to occur in older dogs, most often female, and more frequently in certain breeds such as Scotties and Shelties.

Dogs can develop several different types of bladder tumors, including cancer of the muscle wall and cancer of the inner lining cells of the bladder. Cancer of the lining cells, called transitional cell carcinoma, is the most common type of tumor of the urinary bladder in the dog. Transitional cell carcinomas are most often malignant tumors that can spread to others areas of the body, but also cause serious problems before they spread.

Envision the urinary bladder as a water balloon, with the neck of the bladder being equivalent to the area where one would fill the balloon or release the water. Transitional cell carcinomas usually grow in the area of the “neck” and make it difficult for patients to urinate, because the tumor obstructs the outflow from the bladder into the urethra and to the outside the body.

The symptoms owners notice in dogs with tumors of the urinary bladder resemble those seen in dogs with urinary tract infections. Fortunately, tumors of the urinary bladder are much less common than urinary tract infections. Dogs with bladder cancer will attempt to urinate frequently, but they may only produce small amounts of urine at each attempt, because the tumor may block the outflow tract. Dogs with infections of the urinary bladder also urinate frequently, because the bladder wall undergoes muscle spasms in response to irritation from bacteria. Dogs with bladder cancer may also have bloody urine due to leaky blood vessels in the tumor, and they may develop secondary infections.

As is true for many cancers, by the time owners recognize these signs, the tumor is often fairly large. In the advanced stages, bladder cancer may be acutely life-threatening, because the tumor can completely impede the dog’s ability to urinate, or it can result in kidney dysfunction due to partial urinary obstruction.

Treatment of dogs with bladder cancer is difficult and, in the past, has rarely been successful. This is because the tumors are usually quite advanced by the time they’re detected. It’s usually not possible to surgically remove the entire tumor. Radiation therapy may be effective at killing the tumor cells, but it causes severe injury to the surrounding normal bladder tissues. The side effects of the radiation therapy can lead to clinical signs that are as bad — or worse — than those caused by the tumor itself.

When bladder tumors are identified at a very early stage, they can be treated using photodynamic therapy. Photodynamic therapy involves the use of compounds that make the tumor cells sensitive to intense light. The cells are then destroyed using laser light. However, photodynamic therapy is only effective when the tumors are very small, and there are very few places where this treatment is available. Various chemotherapy regimens have been tested to treat bladder cancer, but most have proven unsuccessful in prolonging life.

To improve the outcome of dogs with bladder cancer, Morris Animal Foundation is supporting the work of Dr. Deborah Knapp at Purdue University’s School of Veterinary Medicine. Dr. Knapp is taking a new approach in the use of chemotherapy for dogs with transitional cell carcinomas of the urinary bladder. In the study entitled “Mechanisms of Synergistic Antitumor Activity of Piroxicam and Cisplatin in Canine Cancer,” Dr. Knapp is evaluating a combination of two different drugs, piroxicam and cisplatin. Piroxicam is a non-steroidal anti-inflammatory drug that also appears to have antitumor effects against transitional cell carcinomas. Cisplatin is a chemotherapy drug that has had some activity against tumors of the urinary bladder.

Earlier studies have shown increased antitumor effects when these two drugs are combined against bladder cancer. Unfortunately, each of these compounds has inherent drawbacks and can be toxic even when used individually. Dr. Knapp and her colleagues are studying a treatment protocol combining these two drugs in order to determine if the tumors can be controlled or eradicated without harmful toxicity. If successful, this treatment could prolong the lives of dogs with bladder cancer while maintaining a good quality of life.


Rob Hilsenroth, DVM, is Executive Director of Morris Animal Foundation. This nonprofit organization sponsors animal health studies at veterinary schools and institutions throughout the U.S. and in other parts of the world. All annual unrestricted contributions to the foundation support health programs — not the cost of administration or fund-raising.

If you’d like to make a contribution, write Morris Animal Foundation, 45 Inverness Drive East, Englewood CO 80112. For more information, call (800) 243-2345 or visit http://www.morrisanimalfoundation.org/

New treatments for congestive heart failure

Congestive heart failure is when the heart weakens and can no longer work efficiently. The heart is a superb pump and when it fails, fluid tends to build up — either in the lungs or the abdomen.

There are many new and excellent medical drugs to help the heart beat more efficiently and steadily. What I would like to touch on are some of the dietary and non-drug treatments which are coming to light. Realize though, that many of these treatments are just now being subjected to controlled studies to determine if they truly are helping dogs with cardiac problems.

Some dogs with heart failure are classic couch potatoes — overweight and not active. Obesity can harm your dog’s heart in many ways — just as in people. Hypertension, increased heart rates, and decreased exercise all can occur with obesity, sometimes turning a mild heart problem into a more serious one. Overweight dogs are also much more prone to respiratory problems, which just compound the whole situation. So keep Bowser trim!

At the other end of the spectrum, we see what is called cardiac cachexia. These are dogs who are losing weight, including muscle mass. Poor absorption of nutrients can lead to weakness, a poorly functioning immune system, and even less desire to eat. Dogs may lose their appetite from some of the medications they are taking. Or the decrease in oxygen to the gastrointestinal system (due to the heart disease) can, at the same time, limit their absorption of nutrients and cause a hypermetabolic state. That means you have to pull out all the stops to get dogs with cardiac cachexia to eat the necessary nutrients. Warming food up, home-cooked meals and garlic powder (not garlic salt) all seem to help stimulate appetites.

Dogs with congestive heart failure can also benefit from sodium reduction — just like humans. Retaining extra sodium causes your dog to retain extra fluid and makes it harder for the heart to pump. Normal dog foods have about 0.47% sodium on a dry matter basis. For moderate sodium restriction, you want about 0.2%, and 0.1% or less sodium (dry matter basis) for very severe sodium restriction. Your veterinarian can tell you which foods fit these descriptions, or you can call the pet food makers.

While sodium-restricted pet foods has a reputation for being unpalatable, that is changing. Doing a gradual switchover from Fido’s favorite food can be all that is required. Do beware of treats! Many of these have quite a bit of sodium.

Potassium is another dietary component that affects how the heart works. Too much or too little can have serious consequences. Dogs on certain diuretics should have their potassium checked periodically. Kidney problems can show up when dogs are on a wide combination of diuretics, sodium restriction and medications to enhance the pumping of the heart. Remember, never change your dog’s drugs or dosages without first checking with your veterinarian.

L-carnitine is a dietary supplement that shows promise for helping some dogs in heart failure. This is a component of fatty acid metabolism — the way in which heart muscle gets its energy. Originally, this was tried on Boxers with cardiomyopathy (a specific type of heart failure), and it seemed to help. It may take weeks to months to see an improvement, but it’s safe. Expense can be a factor for large dogs, but about 40% of all dogs with cardiomyopathy seem to benefit from some extra carnitine.

Taurine hit the news as a factor in cardiomyopathy in cats. Since the feline research, it’s been tried in dogs with some notable successes. American Cocker Spaniels develop heart failure of a certain type which often responds quite well to a combination of l-carnitine and taurine. While that seems to be breed specific, Golden Retrievers with heart failure are now being studied in the hopes that taurine may help them, too. (Chicken is high in taurine.)

Two promising nutraceuticals (nutrients which may have medical benefits, but are not prescription at this time) are fish oils (with high levels of omega-3 fatty acids) and Coenzyme Q. These are supplements which have been shown to help some people and are now being tried on pets. The advantage to many of these nutraceuticals is that they seem to be very safe — so even if they don’t help, they shouldn’t hurt.

If your dog is diagnosed with congestive heart failure, this will give you some additional therapies to discuss with your veterinarian. While the treatments mentioned above won’t replace many cardiac drugs, they may help to increase the length and quality of your pet’s life. And that’s something we all strive for.

New cancer research for pets

Results from two recent surveys conducted by Morris Animal Foundation report cancer as the leading cause of disease-related death for dogs in the United States. With ownership of these companion animals rising to more than 55 million (1997 U.S. Pet Food Institute statistics), dog owners need to learn how to detect the symptoms of cancer and understand prevention techniques in order to help their canine family members lead healthier, happier lives.

To pinpoint pet owners’ concerns regarding their animals’ health and well-being, Morris Animal Foundation conducted two animal health surveys to help guide the Foundation in meeting the health needs of animals through advances in veterinary medicine. The first survey appeared in our own newsletter, Animal News. The second survey was conducted by the Foundation with the cooperation of Veterinary Information Network Inc. and its Pet Care Forum on America Online. In both surveys, dog owners identified cancer as the leading health concern facing their pet. Cat owners responding to the online survey concurred. To address this concern, the Foundation is funding 13 studies this year which focus on various aspects of canine cancer.

Any animal can get cancer. Therefore, it’s important for you to have your veterinarian perform routine and thorough physical examinations on your pets yearly or any time your dog or cat appears to be sick. Older animals should be examined twice a year.

The cause of most cancers is unknown, making prevention difficult. However, spaying or neutering can decrease the risk of breast or prostate cancer in your dog. As is the case in humans, the sooner you detect cancer in your pet, the better the chances are that it can be successfully treated.

The most common visible sign of cancer is a lump or bump. However, tumors involving internal organs are not visible. Other symptoms to watch for are behavioral changes such as inactivity or unwillingness to play. The onset of cancer may also be accompanied by weight loss or gain, diarrhea, or vomiting. With some dogs, clinical signs are so slight, you might not notice anything. That’s why routine physical examinations by your veterinarian are so important.

Not too many years ago, a diagnosis of cancer meant a sure death for most dogs. Things have changed. The good news is that advances in veterinary medicine have allowed for more treatment options. Many regimens have been improved and may also be used together to increase the number of these treatment options. New approaches under development continue to improve the veterinarian’s ability to treat this dreadful disease. Depending on the type of cancer, treatments such as surgery, chemotherapy, radiation, nutritional therapy, immunotherapy, gene therapy, or a combination may be used.

The bad news is that, unfortunately, there are many cancers that simply cannot be cured. While we can extend and improve the quality of life in many instances, the cancer still wins in far too many cases.

Morris Animal Foundation continually works with scientists to find new ways to fight this disease and help provide a healthier tomorrow for your furry friends. To date, the Foundation has sponsored nearly 40 studies that address existing canine cancers, as well as possible treatments. Through these studies, the Foundation provides veterinarians with advances in diagnostic procedures, improved understanding about cancer and its progression, and new methods of treatment.

Rob Hilsenroth, DVM, is Executive Director of Morris Animal Foundation. This nonprofit organization sponsors animal health studies at veterinary schools and institutions throughout the U.S. and in other parts of the world. All annual unrestricted contributions to the foundation support health programs — not the cost of administration or fund-raising.

If you’d like to make a contribution, write Morris Animal Foundation, 45 Inverness Drive East, Englewood CO 80112. For more information, call (800) 243-2345or visit http://www.morrisanimalfoundation.org/

Pain control

There’s no question that dogs feel pain. But because they are the descendants of wolves, they often attempt to hide their pain to avoid showing weakness. Since they have different degrees of stoicism and tolerance to pain, it can sometimes be challenging to pinpoint the source of the pain.

Only when we identify subtle signs of the pain can we provide relief from discomfort. Less-than-obvious signs include excessive panting, shivering, rapid breathing, a rapid heart rate, elevated body temperature, and frequent changing of position while lying down or sitting. Dogs with ear infections may shake their heads or scratch their ears frequently. They may also lick and chew at painful areas, which might be mistakenly interpreted as itchiness. Since dogs don’t necessarily volunteer what degree of discomfort they’re experiencing, it’s up to owners and veterinarians to figure it out and address the problem appropriately. This is especially true for dogs that have undergone surgery.

Any major surgical procedure that involves entering a body cavity (such as the chest or belly) or cutting into bone warrants pain control medication in some form. The most painful surgeries are those that involve bone penetration, and veterinarians give pain medications before these surgeries, as well as afterwards. The length of time after surgery that pain control is needed is variable. If healing is expected to be prolonged, as with many bone repair procedures, pain relievers are usually administered for several days.

Pain control in dogs is important not only for humane reasons, but also because adequate pain management facilitates a more rapid recovery.

This is especially important in the immediate post-operative phase as a dog is awakened from anesthesia. It helps the dog have a smoother, and in many cases, more rapid recovery. Dogs that have their pain well managed will progress quicker to eating, drinking and getting up to relieve themselves. In addition, these dogs are more likely to be sent home sooner.

Owners need to exercise discretion and common sense, however, when using pain-control drugs for their dogs after surgery. They can actually be harmful to the patient if the dog is feeling so little pain that he tries to resume normal activities too soon. Dogs should be discouraged from too much activity and may even need to be confined until a substantial amount of healing has taken place. This is certainly true for patients that have undergone bone surgery.

Traditional means of pain control in dogs involves the use of pain-relieving (analgesic) drugs. Generally, the most common analgesics used by veterinarians for dogs fall into one of four categories: Non-steroidal anti-inflammatory drugs (NSAIDS), corticosteroids, local anesthetics, and morphine-derived narcotics.

NSAIDS are a large group of analgesic drugs that include aspirin and carprofen, among others. These drugs interfere with some of the biochemical pathways that cause swelling, and in so doing, contribute substantially to pain control. These drugs are useful in controlling mild to moderate pain. But dogs tend to be very sensitive to them and caution in dosing is important in order to avoid stomach ulcers and problems with kidney function.

Corticosteroids are another distinct group of drugs that are very potent anti-inflammatories. They include such drugs as prednisone, dexamethasone, triamcinolone, and others. Corticosteroids can be given in a variety of different ways such as: into a vein, under the skin, into the muscle or joint spaces, or orally. They’re also available as short-acting or long-acting preparations, which adds to their utility. Corticosteroids do have an array of side effects in dogs such as increased drinking, eating, and urination, and can even cause thinning skin and a pot-bellied appearance if used long-term. These effects are reversible, however, and steroids remain a very important group of anti-inflammatory medications for more chronic situations. They’re not generally useful for post-operative pain relief.

Local anesthetics act by blocking the nerves that conduct pain sensations to the central nervous system. They’re very effective in controlling pain, although their effects are generally short-lived. These drugs must be given locally in the region where surgery is being performed. Also, they block nerves that control muscle use, so the dog may not be able to move about well while they’re in effect.

Morphine-based drugs are the most potent analgesic drugs available for use in dogs. These narcotics have no anti-inflammatory properties like the drug classes previously discussed, but rather they interfere with the perception of pain on a neurological level. They generally have no lasting side effects, but they’re extremely powerful and careful dosing practices are essential. They can be given orally, intravenously, or by injection.

The narcotic drug fentanyl acts similarly to morphine, but can be given with a transdermal patch that’s applied to the skin with an adhesive. Narcotics are most effective if given before the pain starts, so they’re often given preoperatively. They have the added benefit of causing drowsiness and decreased activity.

Morris Animal Foundation is supporting a study by Dr. Kris T. Kruse-Elliott of the University of Wisconsin School of Veterinary Medicine. Dr. Kruse-Elliott and her colleagues are investigating the analgesic power of transdermal fentanyl versus administration of morphine in the spinal canal before surgery (called “epidural” administration). Among other important objectives, the veterinarians conducting the study will evaluate the length of analgesia provided by these different means of narcotic administration for dogs undergoing bone surgery. The study results will help veterinarians choose the most appropriate route of administration for pain control drugs in dogs that require bone surgery.

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Rob Hilsenroth, DVM, is Executive Director of Morris Animal Foundation. This nonprofit organization sponsors animal health studies at veterinary schools and institutions throughout the U.S. and in other parts of the world. All annual unrestricted contributions to the foundation support health programs — not the cost of administration or fund-raising. If you’d like to make a contribution, write Morris Animal Foundation, 45 Inverness Drive East, Englewood CO 80112. For more information, call (800) 243-2345 or visit http://www.morrisanimalfoundation.org/