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BY MEGAN TREMELLING, DVM, LVS

Warm weather is back, and dogs all around Wisconsin agree that the best possible way to enjoy it is to go for a swim in our nearly one million acres of fresh water. If you work in a veterinary clinic, you know when the time has come by the aroma of wet fur and dead fish that clings to about 10 percent of your patients. (More if you see a lot of Labradors.)

Swimming is a wonderful activity for dogs. Most of them seem to love it. Indeed, some dogs can hardly be kept out of water when it is available, and water retrieving and dock diving are favorite pursuits for many. Swimming causes very little impact to the joints, which makes it ideal for dogs with musculoskeletal disease or injury. Many dogs that develop joint pain after running and playing on land can tolerate a good deal of swimming with no discomfort. And while it is possible to overdo swimming, like any other exercise, a dog is unlikely to stumble, fall or otherwise injure his limbs. Swimming burns off an enormous amount of energy and is invaluable for those dogs that need a lot of hard exercise to keep them out of trouble.

Unfortunately, taking a dip can have its downsides. Not all dogs can swim. Most of them can manage a dog paddle, and some swim very well. However there are a few who are just too anxious or awkward. Dogs with big heads, like Boston Terriers, are not particularly seaworthy and tend to sink headfirst unless they are strong and determined enough to keep their balance. Dogs with very short faces, like those aforementioned Bostons as well as Bulldogs and Pugs, sometimes have a lot of difficulty breathing even on dry land and may find that the challenge of splashes and brief submersions is more than their breathing can handle. Owners who take their dogs swimming are cautioned to watch them carefully at all times, to call it quits when the dog is getting tired and always be aware for signs of distress. Don’t let your dog swim in rough water. Flotation devices for dogs do exist and should be used as needed, but they are no substitute for vigilant supervision.

Dogs have a tendency to swallow water when they swim and play in it, and this can become a problem. Open water, of course, may contain dead fish, debris, and other things that your dog shouldn’t be ingesting. Shallow lakes and ponds are especially prone to overgrowth with blue-green algae, which can be poisonous to your dog. Pool water usually contains chlorine or other treatments. And even perfectly clean water can be harmful when consumed in enormous excess, resulting in vomiting or metabolic disorders that can be fatal. Do make fresh water available to reduce your dog’s urge to drink potentially contaminated water. Never allow your dog to swim in water that is deep green or contains obvious algae mats. And if your dog is the type that just can’t stop slurping up the water, you will need to put limits on his access to it.

If your dog has allergies or very sensitive skin, swimming should be considered with caution. Moisture can trigger inflammation and yeast infections, especially in ears and on feet. That doesn’t necessarily mean your dog can’t swim, but you will need to take extra caution to rinse her clean afterward, make sure her coat is thoroughly dried, and watch carefully for any evidence of skin or ear problems. See your veterinarian if you notice any skin that is red or oozing, or if your dog is licking excessively or shaking her ears. Your veterinarian may be able to make a plan that will allow your dog to enjoy the water without triggering skin problems.

Lastly, dogs that swim are at risk for a mysterious ailment that was never on the curriculum in veterinary school. Known by various names such as “cold tail” and “limber tail,” it seems to be a sprain or strain of the tail muscles, and occurs in dogs after vigorous activity or exposure to cold weather. Swimming in cold water definitely qualifies. The classic presentation is a Labrador that has spent the day swimming seems fine when he gets out of the water, then is found to be in significant pain a few hours later. The tail hangs limply, as if broken. It is worth seeing a veterinarian to make sure the dog doesn’t actually have a broken tail or other serious injury, and to provide some pain relief, but limber tail isn’t a serious problem. With some rest, the Labrador will soon be sweeping coffee tables clean, as good as new… and ready to get back in the water.

By MEGAN TREMELLING, DVM, LVS

The practice of medicine is always evolving. Like other forms of science, it follows a meandering path, sometimes getting lost in false trails and dead ends but always working toward better understanding, better accuracy, better tools and better outcomes. It can be frustrating for researchers to struggle for years to understand a thing or to find out that something we thought we understood was actually wrong, but the trend is always positive eventually. Nowhere is this more clear than in the state of care for type 1 (insulin-dependent) diabetes mellitus, which occurs in dogs as well as in humans.

Diabetes has been known to physicians since ancient times, but it was not until the 1700s that scientists began to understand how the disorder worked, and it was not until the 1920s that insulin was named, isolated and purified to a degree that it could be used to treat diabetes effectively.

Dogs have long been part of diabetes research. The Canadian researchers who first developed the use of insulin worked with dogs before attempting the treatment on humans. Unfortunately, dogs’ early role was exclusively as research subject. In the days before animal welfare regulations were enacted, dogs could and did suffer terribly for the sake of knowledge. The silver lining to this grim cloud is that as companion animal medicine became more established, the knowledge gained could be applied to pets as well as to their owners. By the 1940s, veterinary journals were reporting on the diagnosis and treatment of naturally occurring diabetes in dogs. As the care for humans with diabetes has improved, so too the care for pets with diabetes has improved.

For the management of human diabetes, several types of insulin are made, varying mostly in how quickly they are absorbed and how long they last. This allows veterinarians some options in the choice of insulin therapy for dogs.

Another important development in diabetes care has been an improved ability to measure glucose levels in the urine and, later, in blood. Now, instead of choosing insulin doses on the basis of clinical signs, doctors can calculate appropriate doses of insulin that are customized to their patients. For many years, humans with diabetes have used home blood glucose monitors, obtaining small samples of blood from their fingertips with lancet devices designed for the purpose. It is an unpleasant but very beneficial part of diabetes management, and all humans with diabetes who have access to modern medical care are taught to do it. Unfortunately, home monitoring of blood glucose in pets has not become universal.

The obstacles to home monitoring of blood glucose in dogs are several. In the first place, obviously, dogs don’t have fingertips. It is possible for an owner to obtain blood samples at home, using the lancet devices on their dogs’ ears or pads, though some dogs tolerate this procedure better than others. The second challenge, and perhaps more important, is that it can be challenging for veterinarians to teach owners how to correctly interpret the data they obtain. Humans with diabetes get immediate feedback in the form of their physical condition. Low blood glucose and high blood glucose both cause symptoms that often can be recognized and treated before they become too severe. While we think it likely that dogs can feel their lows and highs in a similar fashion, they can’t tell us about it. This means that attempting to keep their blood glucose under very tight control can backfire and cause more serious problems. I know veterinarians who refuse to have their clients check blood glucoses at home because too many clients in the past have misinterpreted the data and caused inadvertent harm to their pets.

How then do veterinarians manage pets with diabetes? We rely on clinical signs and some in-hospital testing. A test called a glucose curve requires the pet to spend the day at the veterinarian’s office having blood drawn frequently for glucose testing; then the veterinarian assesses the information and makes recommendations on how to dose insulin. This test has some serious limitations. A glucose curve paints a picture of one day only, while dogs, like humans, vary day to day, so the glucose curve may give too small a picture. We also use a blood test called fructosamine (similar to the A1C test used in humans) that gives one number to reflect average blood glucose over several weeks, but that may be too big a picture; it doesn’t give details about what time the glucose decreases, how long it stays down or when it goes up.

Enter the newest development in canine diabetes management: continuous glucose monitoring.

Continuous glucose monitors (CGM) have been used for humans for years. They consist of a tiny sensor that is implanted under the skin along with the accompanying equipment to record the information obtained. Glucose readings can be obtained about every five minutes. Many humans with diabetes wear a CGM every day, using the constant stream of glucose readings to guide their insulin therapy. In some cases, the CGM can be paired with an insulin pump so that the human doesn’t even have to intervene to treat highs and lows; it is done automatically.

Recently, veterinarians have begun to adopt the use of CGM for their patients. There were some bugs to work out since some of the systems designed for human use did not work well on veterinary patients, but improvement has been made, and there are now CGMs that are proven to be accurate in dogs, small enough to be used on even tiny dogs, and affordable for owners. There is no need for a dog to wear a CGM all the time. Rather, veterinarians place a CGM on a patient and leave it for a few days to a week, collecting data as the dog goes about its usual routine at home. Then the veterinarian can use all this information to make better recommendations about insulin use.

CGM is blazing new trails in the care of pets with diabetes. We can hardly wait to see what the next technical breakthrough brings us!

By MEGAN TREMELLING

Nobody wants fleas and ticks on their dog. Even people who don’t like spending a lot extra on caring for their dogs don’t want those parasites getting into their homes and biting the humans. Therefore, valuing your dogs’ health and comfort and preventing external parasites is an important part of their overall care. Many people were worried to hear that the FDA had issued an alert in September about a potential danger associated with some flea and tick products that are part of the isoxazoline group: Nexgard (afoxolaner), Bravecto (fluralaner), Simparica (sarolaner) and Credelio (lotilaner).

What exactly is the problem? It seems that some dogs that have been treated with isoxazolines have developed neurologic symptoms, including tremors, ataxia (wobbly gait) and seizures. It is important to understand that millions of doses of these medications have been given to dogs, and that the fact that some dogs developed neurologic signs does not prove that the symptoms were always, or ever, caused by the medication. After all, some of those dogs probably broke a toenail after receiving the treatment, too. The reason this is different is that it is possible that in some cases the medication did cause the problem. We just don’t know enough to be sure. As with every new group of drugs, pre-release clinical studies can only teach us so much, and we learn much more when the medications are approved and used in large numbers of pets with a wide variety of concurrent medical conditions and medications on board. The FDA has more data on these medications than anyone else, and so far their official word is that “the isoxazoline class [is] safe and effective for dogs and cats.”

To get to a more complete understanding, veterinarians are researching possible adverse effects from isoxazolines and similar drugs, including neurologic changes and vision changes. In the meantime, for very young dogs and for dogs that have a history of seizures, tremors, ataxia, or vision loss, isoxazolines may not be the best choice. For dogs with no history of those problems, there is less reason to believe that these medications cause any significant danger.

As with so many things in life, all medical treatments come with risks and benefits. Veterinarians think in terms of minimizing risk because it is impossible to eliminate it. Isoxazolines have the advantage of being very convenient and very effective at killing fleas and ticks and, for most dogs, the benefits far outweigh the risks. I use one for my own dog.

Of course, if you are not comfortable using an isoxazoline for any reason, you should talk to your veterinarian about whether it is the right choice for your dog because many other options exist, with their own benefits and risks. If you think your dog may be having problems caused by an isoxazoline, you need to talk to your vet about that, too. It isn’t as simple as saying “it’s safer not to give the medication” because most of the time that just isn’t true. The benefits of flea/tick medications are enormous and very well documented; they reduce sickness and death from very common diseases that are transmitted by these parasites.

Stories like these sometimes cause people to reach for “natural” remedies in hopes that they will be safer. Unfortunately, they can be, in some cases, far more dangerous than carefully-tested and properly-prescribed medications. Herbal extracts and essential oils may have their uses, but flea and tick control is not among them. On the other hand, harmful effects, including death, are well-documented, especially when used incorrectly. Safety aside, I do not condone putting anything with a strong smell on your dog if you can help it. A dog’s nose is so sensitive that applying any strong smell to their bodies, where they cannot get away from it, is unlikely to be appreciated.

You may feel that your dog is at low risk for getting fleas and ticks, but if he ever sets paw on the ground or comes in contact with dogs that do, then he has the potential to be exposed to them no matter how meticulous your yard care. Never seen a flea or tick on him? You might not; they are pretty good at hiding. However your veterinarian can tell you whether you have a problem and help you find the solution that is right for your pet.