With April Showers Come… Stagnant Pools of Water and Breeding Mosquitoes

Heartworm Disease in Dogs

What causes heartworm disease?

Heartworm disease or dirofilariasis is a serious and potentially fatal disease. It is caused by a blood-borne parasite known as Dirofilaria immitis.

Adult heartworms are found in the heart and adjacent large blood vessels of infected dogs. Rarely, worms may be found in other parts of the circulatory system. The female worm is 6 – 14″ long (15 – 36cm) and 1/8″ wide (5mm). The male is about half the size of the female. One dog may have as many as 300 worms present when diagnosed.

Adult heartworms may live up to five years and, during this time, the female produces millions of offspring called microfilaria. These microfilariae live mainly in the small vessels of the bloodstream.

What is the life cycle of the heartworm?

The life cycle of the heartworm is complicated; the parasite requires the mosquito as an intermediate host before it can complete its life cycle in the dog. As many as 30 species of mosquitoes can transmit heartworms.

The life cycle begins when a female mosquito bites an infected dog and ingests the microfilariae during a blood meal. The microfilariae develop further for 10 – 30 days in the mosquito’s gut and then enter its mouthparts. At this stage, they are infective larvae and can complete their maturation when they enter a dog. The infective larvae enter the dog’s body when the mosquito bites the dog. They migrate into the bloodstream and move to the heart and adjacent blood vessels, maturing to adults, mating, and reproducing microfilariae within 6 – 7 months.

Where is heartworm disease found?

Canine heartworm disease occurs all over the world. In the United States, it was once limited to the south and southeast regions. The highest numbers of reported cases are still within 150 miles of the Gulf of Mexico and the Atlantic Ocean coastlines and along the Mississippi River and its tributaries. However, the disease is spreading and is now found in most regions of the United States, including California, Oregon and Washington. In Canada, the disease is problematic in areas where mosquitoes are prevalent, such as along waterways and coastlines in many provinces. The greatest number of cases in Canada occurs around the southern Great Lakes.

How is heartworm disease spread?

Since transmission requires the mosquito as an intermediate host, the disease is not spread directly from dog to dog. Spread of the disease therefore coincides with mosquito season, which can last year-round in many parts of the United States. The number of dogs infected and the length of the mosquito season are directly correlated with the incidence of heartworm disease in any given area.

The mosquito usually bites the dog where the hair coat is thinnest. However, having long hair certainly does not prevent a dog from getting heartworms.

What do heartworms do to the dog?

It usually takes several years before dogs show clinical signs of infection. Consequently, the disease is diagnosed mainly in two to eight year old dogs. The disease is rare in dogs less than one year of age because the microfilariae take five to seven months to mature into adult heartworms after infection. Unfortunately, by the time clinical signs are seen, the disease is usually well advanced.

 

Adult heartworms: Adult heartworms cause disease by clogging the heart and major blood vessels leading from the heart. They also interfere with the valve action in the heart. By clogging the main blood vessel, the blood supply to other organs of the body is reduced, particularly blood flow to the lungs, liver and kidneys, causing these organs to malfunction.

The signs of heartworm disease depend on the number of adult worms present, the location of the worms, the length of time the worms have been in the dog and the degree of damage that has been sustained by the heart, lungs, liver and kidneys.

The most obvious clinical signs of heartworm disease are a soft, dry cough, shortness of breath, weakness, nervousness, listlessness and loss of stamina. All of these signs are most noticeable following exercise, when some dogs may even faint or become disoriented. Your veterinarian may notice abnormal lung and heart sounds when listening to the chest with a stethoscope. In advanced cases, congestive heart failure may be apparent and the abdomen and legs will swell from fluid accumulation. There may also be evidence of weight loss, poor condition and anemia. Severely infected dogs may die suddenly during exercise or excitement.

 

Microfilariae (immature heartworms): Microfilariae circulate throughout the body but remain primarily in the small blood vessels. Because they are about as wide as the small vessels, they may block blood flow in these vessels. The cells being supplied by these vessels are then deprived of the nutrients and oxygen normally supplied by the blood. Microfilariae primarily injure the lungs and liver. Destruction of lung tissue leads to coughing. Liver injury leads to cirrhosis of the liver, causing jaundice, anemia and generalized weakness. The kidneys may also be affected and allow toxins to accumulate in the body.

How is heartworm disease diagnosed?

In most cases, one or more simple blood tests will diagnose heartworm disease. Further diagnostic tests are essential to determine if the dog can safely undergo heartworm disease treatment. Some or all of the following diagnostic procedures are recommended before treatment is started:

Serological test for antigens to adult heartworms (antigen test, ELISA or SNAP test): This test is performed on a blood sample.  It is the most widely used test because it detects antigens (proteins) produced by adult heartworms. It can be positive even if the dog does not have any microfilariae in the bloodstream (approximately 20% of cases). Dogs with less than four or five adult heartworms may not have produced enough circulating antigen to produce a positive test result, so there may be an occasional false negative result in dogs with a low burden of parasites, or in the early stages of infection. Because the detected antigen is only produced by the female heartworm, a population of only male heartworms will also give a false negative. Therefore, there must be at least four to five female worms for a positive result by this test.

Blood test for microfilariae (microscopic or Knott’s test):

A blood sample is centrifuged and then examined under the microscope for the presence of microfilariae. If microfilariae are seen, the test is positive. The number of microfilariae seen gives a general indication of the severity of the infection. However, the microfilariae will be found in the bloodstream in greater numbers in the summer months and in the evening, so sampling time can affect this test. Approximately 20% of dogs do not test positive, even though they have heartworms, because their immune system has acquired the ability to destroy the microfilariae. Also, there is another blood parasite that is fairly common in dogs that can be hard to distinguish from heartworm microfilariae. For these reasons, the antigen test is preferred for diagnosis.

There are other tests that should be performed before initiating treatment, including a CBC, chemistry profile, thoracic radiographs, ECG, and echocardiography.

How is heartworm disease treated?

There is some risk involved in treating dogs with heartworms, although fatalities are rare.

When some dogs are diagnosed, they have advanced heartworm disease. This means that the heartworms have been present long enough to cause substantial damage to the heart, lungs, blood vessels, kidneys and liver. A few of these cases will be so advanced that it will be safer to treat the organ damage rather than risk treatment to kill the heartworms. Dogs in this condition are not likely to live more than a few weeks or months. Your veterinarian will advise you on the best treatment approach for dogs diagnosed with advanced heartworm disease.

 

Treatment to kill adult heartworms:

An injectable drug to kill adult heartworms is given. It kills the adult heartworms in the heart and adjacent vessels. These injections may be divided and given thirty days apart. Your veterinarian will determine the specific injection schedule according to your dog’s condition. Many dogs will also be treated with an antibiotic to combat potential infection with bacteria (Wolbachia) that inhabit the heartworm.

Complete rest is essential after treatment. The adult worms die in a few days and start to decompose. As they break up, they are carried to the lungs, where they lodge in the small blood vessels and are eventually reabsorbed by the body. This resorption can take several weeks to months and most post-treatment complications are caused by these fragments of dead heartworms. This can be a dangerous period so it is absolutely essential that the dog be kept as quiet as possible and is not allowed to exercise for one month following treatment. The first week after the injections is critical because this is when the worms are dying. A cough is noticeable for seven to eight weeks after treatment in many heavily infected dogs. If the cough is severe, notify your veterinarian for treatment options.

Prompt treatment is essential if the dog has a significant reaction in the weeks following the initial treatment, although such reactions are rare. If a dog shows loss of appetite, shortness of breath, severe coughing, coughing up blood, fever or depression, you should notify your veterinarian. Treatment with anti-inflammatories, antibiotics, cage rest, supportive care and intravenous fluids is usually effective in these cases.

 

Treatment to kill microfilaria: Approximately one month following treatment to kill the adults, the dog must return to the hospital for administration of a drug to kill the baby heartworms or microfilariae. Your dog may need to stay in the hospital for the day. Following treatment, your dog will be started on a heartworm preventative.

Newer heartworm treatment protocols use a variety of drugs to kill the microfilariae. Your veterinarian will select the correct drug and administration time based on your pet’s condition.

 

Are any other treatments necessary?

Dogs with severe heartworm disease may require antibiotics, pain relief medications, special diets, diuretics to remove fluid accumulations in the lungs, and drugs to improve heart function prior to treatment for the heartworms. Even after the heartworms have been killed, these dogs may require lifetime treatment for heart failure. This includes the use of diuretics, heart medications such as ACE-inhibitors, beta-blockers or cardioglycosides, and special low-salt diets.

What is the response to treatment and prognosis?

Dog owners are usually pleasantly surprised at the improvement in their dog following treatment for heartworms, especially if the dog had been demonstrating any clinical signs of heartworm disease. Many dogs display renewed vigor and vitality, improved appetite and weight gain.

How can I prevent my dog from getting heartworms?

You can prevent your dog from getting heartworms by using a heartworm preventive. When a dog has been successfully treated for heartworms, it is essential to begin a heartworm prevention program to prevent future recurrence. With the safe and affordable heartworm preventives available today, no pet should ever have to endure this dreaded disease.  If your dog is not already on a heartworm prevention program, please see your veterinarian for more details.

What about my cat?  Can cats get heartworm disease?

Yes.  Cats, however, are usually only infected with a few adult worms, and as indicated diagnosis requires at least a couple adult female worms.  As a result, the test for antigen produced by adult females will most likely result in a false negative in a cat infected with heartworms.  Clinical signs in cats are often vague.  Prevention is important in cats as well.  Even indoor only cats can be infected, as mosquitoes can get in the home.

Heartworm disease is easy to prevent.  Please speak to your veterinarian about heartworm prevention for both your dog and cat.

 

Ernest Ward, DVM with modifications and additions by Kristen Ferguson, DVM

© Copyright 2009 Lifelearn Inc. Used and/or modified with permission under license.

My, what stinky breath you have…

Dental Disease in Dogs and Cats

February is National Pet Dental Health Month.  Just like with people, dental care is an important part of your pet’s health, and should be focused on all year round.  

I was unaware that dogs and cats have dental problems. Is it common?

Dental disease is one of the most common medical conditions seen by veterinarians. Over 68% of all dogs over the age of three are estimated to have some form of periodontal or dental disease.  Approximately two-thirds of cats over three years of age have some degree of dental disease. The most common problems are due to periodontal disease, gingivitis and cervical neck lesions, also called oral resorptive lesions.

Few pets show obvious signs of dental disease. It is up to the pet’s family and veterinarian to uncover this hidden and often painful condition.

Are dental problems the same in pets and people?

No. In man, the most common problem is tooth decay, which, due to the loss of calcium from the enamel, results in painful, infected caries (also called cavities). In the dog and cat, tooth decay represents less than 10% of all dental problems. The most common dental problems seen in pets are caused by periodontal disease.

What is periodontal disease?

Periodontal disease is a term used to describe inflammation or infection of the tissues surrounding the tooth. Accumulation of tartar and calculus on the teeth causes gum recession around the base of the tooth. Infection soon follows and the gums recede further, exposing sensitive unprotected tooth root surfaces and the bony tooth sockets Left untreated, the infection spreads deep into the tooth socket, destroying the bone. Ultimately, the tooth loosens and falls out.  If the disease is caught at an early stage and a thorough veterinary dental scaling and polishing performed, most of the teeth and gums will have a full recovery.Once periodontal disease starts the degenerative changes to the tooth and its support structures cannot be reversed. These changes make it easier for more plaque and tartar to collect, resulting in further disease.

How does tartar form and why is it a problem?

The mouth is home to thousands of bacteria. As these bacteria multiply on the surfaces of the tooth, they form an invisible layer called plaque or biofilm. Some of this plaque is removed naturally by the pet’s tongue and chewing habits. If allowed to remain on the tooth surface, the plaque thickens and becomes mineralized. Mineralized plaque forms tartar and as the tartar thickens further it becomes calculus. The tartar accumulates above and below the gumline and presses on the gums, causing inflammation called gingivitis.
As the oral infection progresses, tonsillitis and pharyngitis can also occur. The bacteria can also be absorbed into the blood stream and be carried to other organs. “Bad teeth” can cause infections in the heart valves (endocarditis), kidneys and/or liver.

Can tartar be prevented?

Plaque becomes mineralized in some pets much quicker than in others.  The best way to prevent tartar build-up is regular home care, particularly tooth brushing using toothpaste that is specifically designed to be swallowed. Special dog chew toys and treats may help reduce or delay tartar build-up. Some pet foods have been specifically formulated as dental diets that mechanically assist in plaque removal.

Will feeding dry food remove tartar?

Pet food manufacturers have recently developed new dental diets that can help reduce the formation of plaque and tartar in your pet. Once tartar has formed, it will be necessary to remove it by professional scaling and polishing under general anesthesia.

What are the clinical signs of dental disease?

Certain signs should alert you to the presence of dental disease or other oral problems in your pet. Your pet may show a decreased interest in food or approach the food bowl and then show a reluctance to eat. It may chew with obvious discomfort, drop food from the mouth, or swallow with difficulty. The pet may drool excessively, and the saliva may contain blood. The pet may have halitosis, or an unpleasant breath odor. In some cases, pets may paw at their mouths or shake their heads. A reluctance to eat may lead to weight loss, which can become quite marked. Many pets will refuse dry food and demonstrate a preference for moist or canned foods. Dental disease and oral pain may account for the “finicky appetites” that some pets display.

What is involved with a routine dental cleaning?

A routine dental cleaning involves a thorough dental examination, followed by a dental scaling and polishing to remove the tartar and invisible plaque from all of the tooth surfaces. Your veterinarian will discuss the specific pre-dental recommendations for your pet.
Once your pet is anesthetized, your veterinarian will thoroughly examine the mouth, noting the alignment of the teeth and the extent of tartar accumulation both above and below the gumline. If periodontal disease is severe, it may not be possible to save badly affected teeth, which may need to be extracted. Next, tooth scaling will be performed using both traditional hand scalers and ultrasonic cleaning equipment to remove all traces of tartar, both above and below the gum line. The tartar below the gum line causes the most significant gum recession and it is extremely important that it is removed thoroughly. After scaling, the teeth are polished to remove microscopic scratches in order to help prevent subsequent plaque build-up. Special applications such as fluoride, antibiotic preparations and cleaning compounds may be indicated to decrease tooth sensitivity, strengthen enamel, treat bacterial infection and reduce future plaque accumulation.
The procedures that your pet may require will be discussed with you before your pet’s dental cleaning. Since it can be difficult to predict the extent of dental disease in advance of the procedure, it is imperative that your veterinarian is able to reach you during the procedure to discuss any additional treatment that may be necessary.

Why can’t I just remove the tartar and plaque with a dental scaler?

Although you can remove the tartar that has accumulated above the gumline in some pets that are extremely co-operative, there are three problems with doing this. First, only the tartar above the gumline is removed, leaving behind the material below the gumline, which will continue to cause periodontal problems. Second, it is not possible or safe to clean the inner surfaces of the teeth properly in a conscious animal. Third, the use of any instrument on the tooth enamel will cause microscopic scratches on the surface, ultimately damaging the tooth surface and leading to further disease. (This is the reason why your dental hygienist always polishes your teeth after removing the tartar with dental instruments).

How can I prevent tartar accumulation after the procedure?

Plaque and tartar begin forming in as little as six hours after your pet’s dental cleaning. A home dental care program including regular tooth brushing is a must for all pets. Your veterinarian will provide you with detailed instructions on how to brush or rinse your pet’s teeth.  In addition, or as an alternative to brushing, a range of antibacterial mouthwashes and gels can be applied to the teeth and mouth to reduce the number of bacteria present. Please ask your veterinarian for further details regarding the recommended dental products for your pet.

Can I use human toothpaste?

Absolutely not. Human dentifrice or toothpaste should never be used in pets. Many human toothpastes and other oral hygiene products contain xylitol, a sugar substitute that is safe for use in humans but highly toxic in dogs.
Even if there is no xylitol in the toothpaste, these foaming products contain ingredients that are not intended to be swallowed and that could cause internal problems if they are swallowed. Human products often contain higher levels of sodium than your pet requires, which is another reason why they should not be swallowed.
You should also avoid using baking soda to clean your pet’s teeth. Baking soda is alkaline and if swallowed can upset the acid balance in the stomach and digestive tract. In addition, baking soda does not taste very good, and may cause your pet to be uncooperative when you try to brush its teeth.

Why is pet toothpaste recommended?

Numerous pet toothpastes that are non-foaming and safe to be swallowed are available in flavors that are appealing to dogs; depending on the brand, you may be able to find flavors such as poultry, beef, malt or mint. If you use a product that tastes good, your pet will be more likely to enjoy the whole experience. In addition to the pleasant taste, many of these doggy toothpastes contain enzymes that are designed to help break down plaque chemically, thus reducing the time you need to spend actually brushing your dog’s teeth.

So what are you waiting for?  If your pet has stinky breath or obvious tartar and gingivitis, schedule a dental cleaning with your veterinarian today!

Ernest Ward, DVM, with additions and modifications by Kristen Ferguson, DVM.
© Copyright 2010 Lifelearn Inc. Used and/or modified with permission under license.

Winter Weather Hazards-Part 2 of 2

Ethylene Glycol Poisoning

What is ethylene glycol?

Ethylene glycol, a sweet-tasting, odorless liquid, is the active ingredient in antifreeze. Ethylene glycol can also be found, in lower concentrations, in some windshield de-icing agents, hydraulic brake fluid, motor oils, solvents, paints, film processing solutions, wood stains, inks, printer cartridges, etc.

How do animals get ethylene glycol poisoning?

Dogs and cats are attracted to ethylene glycol by its sweet taste. Many animals will voluntarily drink ethylene glycol if antifreeze is spilled or leaks onto garage floors or driveways. Ethylene glycol has a very narrow margin of safety – which means only a tiny amount can result in severe poisoning. As little as one eighth of a teaspoon per pound of cat can result in fatalities in cats, while as little as half a teaspoon per pound of dog can result in fatalities in dogs.

What are the signs of ethylene glycol poisoning?

Early signs of ethylene glycol poisoning are called “Stage 1”, and can be seen within 30 minutes of toxin ingestion.  The signs include lethargy, vomiting, incoordination (walking drunk), excessive urination, excessive thirst, hypothermia (low body temperature), seizures, and coma.  In “Stage 2” (which occurs 12 to 24 hours after ingestion), some of the signs seem to dramatically improve, luring pet owners into a false sense of security. However, during this stage, pets become dehydrated, and develop an elevated breathing and heart rate.  “Stage 3” occurs 12-24 hours after ingestion in cats, and 36-72 hours after ingestion in dogs. At this stage, signs of severe kidney dysfunction, which is characterized by swollen, painful kidneys and the production of minimal to no urine, may occur. Progressive depression, lethargy, lack of appetite, vomiting, seizures, coma, and death may be seen.

If you suspect that your pet has consumed ethylene glycol, or is exhibiting early symptoms, bring it to your veterinarian immediately.  Do not wait; time is of the essence and immediate treatment is essential! Left untreated, the animal will die. Dogs must be treated within 8-12 hours of ingesting antifreeze, while cats must be treated within 3 hours of ingesting antifreeze, as the antidote only has a narrow time period to work.

How do we confirm ethylene glycol poisoning?

The best way to confirm ethylene glycol poisoning is by measuring the blood concentration of ethylene glycol. A test to determine the blood levels can be done at some veterinary diagnostic laboratories or human hospitals. This testing method is very accurate, but not always available in the middle of the night. In addition, a test kit that can be used in the veterinary clinic is available to detect the amount of ethylene glycol present in the bloodstream. However, these types of tests may not be as accurate, and false positives can be seen (for instance, certain agents other than ethylene glycol interact with the test, like propylene glycol, glycerol, mannitol, isopropyl alcohol, sorbitol, etc.). Also, if this test kit is run too late, it may test falsely negative; in other words, since peak levels of ethylene glycol are detected in to the first 1- 6 hours after ingestion of the toxin, it is important that this test kit be used early in the course of suspected poisonings. By as early as 24 hours after ingestion, insufficient ethylene glycol remains to allow detection on this blood test; however, the damage to your pet’s body from ethylene glycol has already occurred.

Are there other tests that can indicate ethylene glycol poisoning?

Ethylene glycol is converted by the liver into toxic byproducts that are damaging to the kidneys. This damage can be identified in a serum biochemistry profile by increases in the levels of creatinine and BUN (blood urea nitrogen) that are normally removed from the blood by the kidneys. However, these tests are not specific for ethylene glycol toxicity, and by the time these blood tests shows evidence of kidney failure, the prognosis is grave to poor (since it is already too late to treat with the antidote).  Acidosis (acidic blood) can also be detected through the biochemistry profile.  A urinalysis may also confirm ethylene glycol poisoning and underlying kidney damage by the presence of dilute urine containing blood, protein, cellular casts (plugs of cells which have taken the shape of dying tubules in the kidneys), and calcium oxalate crystals (which are seen with  ethylene glycol poisoning).  Lastly, a special lamp (Wood’s lamp) can sometimes be used to examine the urine, muzzle, and paws of the patient to look for the presence of the dye (which is added to automotive antifreeze); this dye is excreted up to 6 hours after ingestion.

When in doubt, if you suspect your pet has ingested ethylene glycol, immediate veterinary attention is imperative; as the prognosis is very poor once clinical signs have developed. Again, as the time period within which to treat pets with the antidote (fomepizole) is only 3 hours in cats and 8-12 hours in dogs, it is imperative that you see a veterinarian immediately. When in doubt, you or your veterinarian can contact Pet Poison Helpline (800-213-6680) 24/7 for life-saving assistance in managing a poisoned patient.

Cold Weather Tips for the Outdoor Pet       

I have pets that is housed outside.  How do I keep them safe in the winter?
Make sure you have appropriate shelter from the wind and precipitation. Good bedding is also key; straw or blankets are a good option.  Avoid electric heating due to the risk of fire.

Fresh water is important at all times for pets, therefore in the frigid winter it is necessary to check the water bowl for freezing muliple times per day. Heated water bowls are another option.

Outdoor pets may need additional calories to help maintain their body temperature.  If you keep a pet outdoors, please consider consulting with your veterinarian to ensure you are doing everything to keep your pets safe. If you are in doubt about leaving a pet outside due to temperature or precipitation, it is better to err on the side of caution and keep it inside.

Kristiina Ruotsalo, DVM, DVSc, Dip ACVP & Margo S. Tant BSc, DVM, DVSc & Justine A. Lee, DVM, DACVECC, with additions by Kristen Ferguson, DVM
© Copyright 2012 Lifelearn Inc. Used and/or modified with permission under license.

Oh the weather outside is frightful…

Winter Weather Hazards—Part 1 of 2

Snow covering the ground.  Ice shining the streets.  Blustery wind cutting to the bone.  With the winter weather come a few hazards to your pets that you should be aware of.

Frostbite in Dogs and Cats

What is frostbite?

Frostbite or congelatio in medical terminology is the damage that is caused to skin and other tissues due to extreme cold. When the environmental temperature drops below 32°F (0°C), blood vessels close to the skin start to narrow or constrict. This constriction of the blood vessels helps to preserve core body temperature by diverting blood toward the core and away from the cooler parts of the body. In extreme cold or when the body is exposed to cold for long periods, this protective mechanism can reduce blood flow in some areas of the body, especially the extremities, to critically low levels. The combination of cold temperature and reduced blood flow can allow the tissues to freeze, causing severe tissue injury.

Where is a dog or cat most likely to get frostbite?
The paws, ears and tail are the most common tissues to be affected. If a pet is wet or damp, these areas are more vulnerable to frostbite.

What are the clinical signs of frostbite?

• Discoloration of the affected area of skin – this discoloration is often pale, gray or bluish
• Coldness and/or brittleness of the area when touched
• Pain when you touch the body part(s)
• Swelling of the affected area(s)
• Blisters or skin ulcers
• Areas of blackened or dead skin

As frostbitten tissues thaw, they may become red and very painful due to inflammation.The clinical signs of frostbite may take several days to appear, and severely frostbitten areas will become necrotic or die. As the tissue starts to die, it changes to a dark blue to black color; then, over a period of several days to weeks, it sloughs or falls off. During this time, pus may form or the tissue may develop a foul smell, due to secondary bacterial infection.
Dogs and cats with heart disease, diabetes mellitus or other conditions that cause reduced blood flow to the extremities are at greater risk for frostbite.

How is frostbite treated?
If you suspect your pet has frostbite, you should seek medical attention immediately. Interim first aid suggestions that you can begin include:

• Move your pet to a warm, dry area as quickly and as safely as possible.
• If your pet is suffering from hypothermia or low core body temperature, treat the hypothermia first. Do this slowly by wrapping its body in warm dry towels or blankets and placing hot water bottles wrapped in towels near its body.
• DO NOT rub or massage the affected area.
• If you are outdoors, DO NOT warm a frostbitten area if you cannot keep it warm. Additional cold exposure or refreezing will more severely injure the tissues.
• You may carefully warm the affected area with warm (NOT HOT) water. The recommended water temperature is 104 to 108°F (40 to 42°C) – at this temperature, you should be able to comfortably place your hand in the warm water. If the water is too hot, you may cause more damage than not using any water at all. You may apply warm water compresses or soak the affected area in a bowl of warm water. DO NOT use direct dry heat such as a heating pad or hair dryer.
• After you have warmed the area, pat it dry carefully and thoroughly.
• While traveling to the veterinarian for further medical treatment, keep your dog warm by wrapping the pet in dry towels or blankets that have been warmed in the clothes dryer.
• DO NOT give any pain medication unless specifically instructed by your veterinarian. Many human pain relievers, including acetaminophen and aspirin can be toxic to pets.

Your veterinarian will examine your pet and treat any other conditions, especially systemic shock or hypothermia. Since the thawing tissues are extremely painful, your pet will probably be given pain medication. Antibiotics are used to prevent secondary bacterial skin infection if tissue necrosis or death is suspected. Some dogs will require amputation of a severely affected body part.

What is the prognosis for frostbite?
The prognosis for frostbite depends on the extent of your dog’s injuries. Mild cases of frostbite usually resolve with little permanent damage while more severe frostbite may result in permanent disfiguration or alteration of the affected tissues. In extreme cases, amputation or surgical removal of the necrotic tissues is required. Your veterinarian will discuss the appropriate diagnostic and treatment plan for your dog.

Ice-Related Musculoskeletal Injuries
With how easy it is for people to slide on the ice, it’s important to be careful when walking your dog outside or letting them loose in dog parks or backyards that may have ice patches.  It is easy for them to splay their legs on a slippery surface and fall.  A fall on ice can result in strained or torn ligaments or tendons, or even fractures.When walking your dog on a leash outside, make sure to go slow.  If your dog becomes lame after a slip on the ice, set up an appointment with your veterinarian.  Do not try any over-the-counter pain medication without consulting your veterinarian, as some medications can be harmful to your pet if given too high of a dose.Please remember, the winter weather can pose some serious threats to your critters.  It is best to keep pets indoors in freezing temperatures to prevent hypothermia, frostbite, and other injuries.  Keep them inside instead—and let them help keep you warm during these cold winter months.

The next blog will focus on some additional cold weather hazards. Stay tuned.

Ernest Ward, DVM, with additions made by Kristen Ferguson, DVM.
© Copyright 2009 Lifelearn Inc. Used and/or modified with permission under license.

A New Year, A New Resolution

On New Year’s Eve every year, many people make New Year’s Resolutions.  These resolutions are goals or promises for that person to make or keep throughout the coming year, and of course vary from person to person.  A common resolution is to lose weight and get in shape for better health and well being.  Working out and eating better are great resolutions to have for yourself, but take a look around your home.  Is there any other member of your family that could benefit from a resolution to lose weight?  If you see a sausage-shaped dog sprawled on the floor, or a soccer ball of a cat napping on the sofa, then perhaps an additional New Year’s Resolution you make this year should be to help your chubby buddy lose weight.

 
I have been told that my pet is obese and must be put on a diet. Is this true?
In people, over two-thirds of all Americans and Canadians are overweight and over one-third (33%) of all adults are obese. Unfortunately, this same number now applies to our pets. Obesity leads to several diseases, both in pets and people. Type II diabetes, heart disease, arthritis, certain forms of cancer, lower urinary tract disease, and hepatic lipidosis can all be weight-related disorders.

What is obesity?
Obesity is generally defined as weighing 30% more than the ideal weight for a given pet. With humans, the ideal weight can usually be determined by consulting weight and height charts. Since there are so many different breeds and body conformations in pets, the ideal weight is determined by using a combination of weight charts and body scoring.

A simplified form of body condition scoring used by your veterinarian will put your pet in one of the following categories: very thin (1), underweight (2), ideal (3), overweight (4), and obese (5).  When your veterinarian says your pet has a BCS (body condition score) of 3 out of 5, then your pet is at an ideal weight.

What is the cause of obesity?
Obesity is the accumulation of excess energy stored as fat. It occurs when your pet receives more calories then he needs and expends. Hypothyroidism may predispose dogs to obesity. Any overweight dog should be tested for hypothyroidism before beginning a weight loss program.  Indoor cats are more prone to obesity, perhaps because they eat more out of boredom, but also because they have less opportunity to stay trim through exercise.  With that being said, cats that roam outdoors are more at risk for contracting and spreading infectious disease and are a nuisance for wildlife.

My pet can’t be obese because he only eats a small amount of food every day.
Obesity often develops insidiously. We think we are feeding our pets only small quantities of food, but tend to forget the treats and table foods. These treats add calories and result in weight gain. A few extra calories a day can add up over time.  Additionally, many owners say they are only feeding one cup of food per day, which doesn’t sound like much until it’s determined that the cup used is a Big Gulp cup from the gas station.

What can I do?
With today’s advances in nutrition, weight loss has never been easier. Your veterinarian will design a safe and effective weight loss program to meet your pet’s lifestyle.  It is better to set realistic goals for weight reduction rather than attempting to force the pet down to a “normal” weight. Usually a 15-20% reduction in weight is a reasonable and achievable target.  Avoid rapid weight loss; weight that is lost slowly is more likely to stay lost!

To help your dog burn more calories, take him on a brisk, thirty-minute walk twice daily. Discontinue feeding table foods and treats. Instead, offer carrots, broccoli or veterinary-approved low-calorie treats.  For cats, try laser pointers and toys that require running or jumping to play with them, and feed low-calorie treats.   

Most pets can lose weight if you adhere to these recommendations. Weight loss in pets and humans requires both reduced caloric intake (eating less) and increased caloric expenditure (more physical activity). The great news is that weight reduction is about 60% diet and 40% exercise. Weight loss is often a matter of diligence and persistence. Remember that the reason you are doing this is to help your pet live as long and healthy a life as possible.  When you decide on your New Year’s resolution(s) this year, please remember your furry family members who cannot make their own.

 

Ernest Ward, DVM with modifications by Kristen Ferguson, DVM
© Copyright 2009 Lifelearn Inc. Used and/or modified with permission under license.

To Give or Not to Give That Wishbone? That is the Question.

Ingestion of Foreign Bodies in Dogs

Dogs are curious by nature. They love to investigate new sights, smells and tastes. Unfortunately, this curiosity can lead them into trouble. Dogs are notorious for swallowing paper, tissues, articles of clothing, sticks, wicker, bones, food wrappers, rocks, and other foreign objects. Many of these objects will pass through the intestinal tract without problem. It is common for dog owners to report finding all sorts of objects in their dog’s stool or vomit.

However, one of the more common and potentially life-threatening conditions seen in veterinary practice is foreign body obstruction. Although most foreign bodies do pass uneventfully through the intestinal tract, if an obstruction occurs for some reason, surgical removal of the blocked object is the only treatment.

With the Thanksgiving Holiday coming up this Thursday, you may have a beggar staring eagerly at you as you get your turkey prepared for the feast.  Not all owners willingly give a bone or ‘people’ food to their pets, but they are good at being sneaky and quickly picking up droppings from the floor!  This blog explains why you should be careful not to let your dogs (or cats!) eat bones or any foreign object.  

How do I know if my pet has ingested a foreign body?

Most pets that have ingested a foreign body will exhibit some of these clinical signs:

• Vomiting
• Diarrhea
• Abdominal tenderness or pain
• Decreased appetite or anorexia
• Straining to defecate or producing small amounts of feces
• Lethargy
• Changes in behavior such as biting or growling when picked up or handled around the abdomen

Objects that can potentially (or likely) cause intestinal obstruction:

• Bones
• Corn cobs
• Fabric (underwear, socks, towels, carpet, etc)
• Balls and other toys
• String/rope
• Anything non-digestible that is too large to pass through the small intestines!

How is it diagnosed?

After obtaining a thorough medical history, your veterinarian will perform a careful physical examination. If a foreign body is suspected, abdominal radiographs (x-rays) will be performed. Several views or a series of specialized x-rays using contrast material (barium or other radiographic dye) will often be necessary. In addition, your veterinarian may recommend blood and urine tests to assess whether the patient’s health has been compromised by the obstruction, or to rule-out other causes of vomiting such as pancreatitis, enteritis, infections or hormonal diseases such as Addison’s disease.

How is an intestinal foreign body treated?
If a foreign body obstruction is diagnosed or suspected, exploratory surgery is generally recommended.    Time is critical since an intestinal or stomach obstruction often compromises or “cuts off” the blood supply to these vital tissues. If the blood supply is interrupted for more than a few hours, these tissues may become necrotic or “die” and irreparable damage or shock may result.

In some instances, the foreign body may be able to pass on its own. In this event, your veterinarian may recommend hospitalization of your dog for close observation, and will perform follow-up radiographs to track the progress of the foreign object.

If any clinical signs are related to an underlying condition, or if diagnostic testing indicates compromised organ systems, these abnormalities will also require treatment.

What is the prognosis?

The prognosis is based on:
1.  the location of the foreign body,
2.  the duration of any obstruction,
3.  the size, shape and characteristics of the foreign body, and
4.  the health status of the pet before foreign body ingestion.

Your veterinarian will provide you with detailed diagnostic and treatment plans as well an accurate prognosis based on your pet’s condition.

In summary…

Please think twice this holiday season before feeding your pets anything that could potentially cause an obstruction, or before giving them a new toy that they may want to eat instead of play with.  While your pets may be hard to say no to, it’s better to err on the side of caution in order to avoid a visit to the vet hospital for an emergency surgery!

 
Ernest Ward, DVM, with additions by Kristen Ferguson, DVM
© Copyright 2009 Lifelearn Inc. Used and/or modified with permission under license.

The Scary Truth About Chocolate

It’s the time of year again when children will soon be running around the streets dressed as ghosts, witches, princesses, pirates, and random animals and cartoon characters. They’ll be bringing home lots of goodies to eat–and hey, as parents/aunts/uncles/grandparents, you have the right to partake as well!  But there is a family member that should not partake in any Halloween chocolate, and that member is the dog!  

Why is chocolate toxic?
Chocolate is toxic to dogs because it contains the methylxanthine theobromine, which is similar to caffeine.  It is used medicinally as a diuretic, heart stimulant, blood vessel dilator, and a smooth muscle relaxant. Theobromine can be poisonous and result in severe clinical signs, especially if untreated.

Toxic doses and clinical signs
Toxic doses of theobromine are reported to be as low as 20 mg/kg, where agitation, hyperactivity and gastrointestinal signs (such as drooling, vomiting, and diarrhea – all which may smell like chocolate) can be seen. At doses > 40 mg/kg, cardiac signs can be seen, and include a racing heart rate, high blood pressure, or even heart arrhythmias. At doses > 60 mg/kg, neurologic signs can be seen, and include tremors, twitching, and even seizures. Fatalities have been seen at around 200 mg/kg (approximately 100 mg/lb), or when complications occur. Other symptoms can include increased thirst, increased urination, and lethargy.  It is also possible to have complications such as aspiration pneumonia from vomiting.  Clinical signs of chocolate poisoning can take several hours to develop, and can last for days due to the long half-life of theobromine.

Different kinds of chocolate=varying amounts of theobromine
The amount of toxic theobromine varies with the type of chocolate. The darker and the more bitter the chocolate, the more dangerous it is to your pets. See the chart below for the amounts of theobromie and caffeine in different kinds of chocolate. White chocolate barely poses any threat of chocolate poisoning, with only 0.25 mg of theobromine per ounce of chocolate (that said, dogs can still get sick from all that fat and sugar, resulting in pancreatitis!). For a medium size dog weighing 50 pounds it would take only 1 ounce of baker’s chocolate or 8 ounces of milk chocolate to potentially show signs of poisoning. 

Amount methylxanthine (mg/oz)
Compound	Theobromine (mg/oz)	Caffeine (mg/oz)
White chocolate	0.25	0.85
Milk chocolate	58	6
Dark, sweet chocolate	130	20
Semi-sweet chocolate chips	138	22
Baker’s (unsweetened) chocolate	393	47
Dry cocoa powder	737	70
Instant cocoa powder	136	15
Cocoa beans	600	600
Cocoa bean hulls	255	NA

Dr. Susan Barrett, Capital Veterinary Referral and Emergency Center, 12/4/2007

 

My dog ate chocolate–now what?
When in doubt, contact your veterinarian or Pet Poison Helpline to see if a poisonous amount of chocolate was ingested to begin with. If so, your veterinarian may want to induce vomiting, provided your dog isn’t showing any clinical signs. If a toxic amount is ingested, you should have your pet examined by a veterinarian immediately. The sooner the theobromine is removed from the body or the pet is stabilized, the better your dog’s prognosis.

 What is the treatment for chocolate poisoning?
Treatment depends on the amount and type of chocolate eaten. If treated early, removal of the chocolate from the stomach by administering medications to induce vomiting and administration of activated charcoal to block absorption of theobromine into the body may be all that is necessary. Activated charcoal may be administered every four to six hours for the first twenty-four hours to reduce the continued resorption and recirculation of theobromine. 
It is very common to provide supportive treatments such as intravenous fluid therapy to help dilute the toxin and promote its excretion. All dogs ingesting chocolate should be closely monitored for any signs of agitation, vomiting, diarrhea, nervousness, irregular heart rhythm, and high blood pressure. Often, medications to slow the heart rate (e.g., beta-blockers) may be necessary to treat the elevated heart rate and arrhythmia.

Lastly, a few other foods poisonous to dogs…
onions, macademia nuts, grapes, raisins, moldy food, avocado, xylitol found in chewing gum

*Pet Poison Helpline is an animal poison control service based out of Minneapolis available 24 hours, seven days a week for pet owners and veterinary professionals who require assistance treating a potentially poisoned pet.  Pet Poison Helpline is available in North America by calling 800-213-6680. Additional information can be found online at www.petpoisonhelpline.com.

 

Ernest Ward, DVM & Justine A. Lee, DVM, DACVECC, Associate Director of Veterinary Services, Pet Poison Helpline
© Copyright 2011 Lifelearn Inc. Used and/or modified with permission under license.