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Lyme Disease in Pets: Signs and Symptoms

5 min read

By Katherine George

According to the Centers for Disease Control and Prevention, 300,000 Americans are inflicted with Lyme disease every year—and that’s only the cases reported by two-legged victims.

Lyme disease is one of the most common tick-transmitted diseases in the world. Lyme disease is caused by a type of bacteria called Borrelia Burgdorferi. Lyme disease is transmitted by slow-feeding, hard-shelled deer ticks, Western black-legged ticks, taiga ticks and sheep ticks, which are difficult to detect as they’re about the size of the period at the end of this sentence.  Usually a pet becomes infected only after the tick has been attached to the dog for at least 18 hours.

The best way to check your dog for ticks is go through your dog’s coat with an air blower (hair dryer). Otherwise brushing the fur or running your hands through his/her coat is a good inspection method too. Especially check under your dog’s ears, head, neck underbelly and feet, as well as to keep an eye out for these 13 symptoms…

1. Inflammation of the Joints

The most obviously sign of Lyme disease in canines is inflammation in the limbs and joints, which shows itself as lameness. This makes it difficult and painful for the dog to move for about a week at a time, and the dog will often walk stiffly with a painfully arched back.

2. Shifting Lameness

Oftentimes, when a dog is afflicted by lameness, the painful inflammation of joints, it will show itself as a condition known as shifting-leg lameness, which is characterized by lameness that alternates from one to the other, with normal function in between bouts of stiffness and pain. In addition to joint swelling, they will feel warm and tender to the touch.

3. Kidney Issues

Untreated Lyme disease almost always leads to kidney issues in dogs, particularly breeds such as Golden and Labrador Retrievers, and Bernese Mountain dogs. Related kidney inflammation, or a condition referred to as glomerulonephritis, will eventually lead to organ dysfunction and complete failure. The signs of kidney issues in dogs include unquenchable thirst, vomiting, diarrhea, loss of appetite, weight loss, increased urination, bloated abdomen, and fluid retention.

4. Tender Joints

However, a small portion of infected dogs do develop sore, painful joints that are sensitive to touch weeks or months after infection. You may notice that your normally active, energetic dog is laying around a lot and would rather stay inside and sleep then go outside and play.

5. Visible Difficulty Moving & Walking

Most dogs are a sad sight when in pain and difficultly moving, walking, climbing, and getting up from a prone position may be your first indication that your healthy dog is sick. Most dogs will be reluctant to move and yelp when they get up quickly. They will also respond to pain with yelping or nipping when an inflamed joint is pressed upon.

6. Depression

Depression may accompany inflammation of the joints, pain, and fatigue. Many of the sick dogs become so depressed that they totally lose their appetites and refuse to eat altogether.

7. Swollen Lymph Glands

Much like humans; dogs’ lymph nodes respond to any type of disease or infection. This is why you might notice swollen lymph nodes at the base of your dog’s) legs (where the lymph glands are located). You may also notice swelling when petting your dog at the sight of the tick bite.

8. Fever

Most times, dogs with Lyme disease won’t show similar symptoms to humans infected with Lyme disease. However, a low grade fever or hyperthermia may occur as a symptom. “As the immune system of a Lyme disease-infected dog is stimulated to fight infection by Borrelia burgdorferi, hyperthermia occurs,” writes PetMD. Your dog may be hot to the touch and he or she may drink more than usual. To tell whether or not your dog is suffering from hyperthermia, the source lists a dog’s normal body temperature at between 100 to 102.5 degrees Fahrenheit. If he or she is infected, they’ll suffer from either intermittent or consistent increases in body temperature.

9. Lethargic

In addition to their difficulty moving around and depression, pets that have been infected with Lyme disease might also be extremely lethargic and weak. This one will be quite noticeable, especially if your pet was quite active before. All dogs need rest, but if a pet seems to be tired and sleepy more than it’s awake and energetic, then there might be something more going on.

According to PetMD, “lethargy occurs as a result of the immune system’s increased efforts to fight the Lyme disease bacteria (Borrelia burgdorferi) through the production of antibodies (immune system proteins) and white blood cells. Body temperature elevation (hyperthermia) is often associated with lethargy.”

10. Loss of Appetite

When we’re not feeling well we tend to lose our appetite, and the same goes for our pets. Due to all the other symptoms caused by Lyme disease including fever, difficulty moving and walking, joint pain, etc, it might not be that surprising that they also will experience a lack of appetite, or as PetMD points out, it’s also considered anorexia. Lyme disease can cause dogs to not want to eat as much or often, or in some cases at all.

“Anorexia can be caused by hyperthermia (elevated body temperature), arthritis (joint inflammation), myalgia (muscle pain), renal (kidney) failure, or other ailments with infection by Borrelia burgdorferi,” writes PetMD.

11. Digestive Tract Issues

In addition to not wanting to eat, PetMD states that some pets will also experience some digestive tract issues like nausea and vomiting, which also contributes to why they’re not eating. “Besides eating less or refusing food, dogs infected with Lyme disease can have other digestive tract upset such as emesis (vomit) or diarrhea related to hyperthermia, renal failure, or other health problems,” writes the source.

12. Drinking More Water

We’ve already discussed how an infected dog’s temperature will rise and cause a fever or hyperthermia. This condition will then cause the pet to want to drink more water to cool themselves down. An excessive thirst for water is referred to as polydipsia, but it can also be stimulated by kidney failure which is sometimes an unfortunate result of a Lyme-disease infection, explains PetMD. This excessive thirst then causes an increased urine output.

“Failing kidneys have a reduced ability to concentrate urine. Ultimately, this failure prompts the affected dog to drink more water as the body tries to excrete the toxins from the blood that would otherwise normally be filtered by the kidney into urine,” writes the source.

13. No Symptoms At All

Sadly, the majority of dogs who become afflicted with Lyme disease don’t show any symptoms until it’s much too late. This is why it’s vital if you live in a tick-prone area to examine your dog regularly for ticks by brushing, petting, and taking your dog to the vet for his or her yearly checkup and Lyme disease test.

Senior Managing Editor

Katherine is the Senior Managing Editor of ActiveBeat and Childhood. She is constantly striving to live a more active and healthy life, from eating healthy, exercising, and just spending more time outdoors. She enjoys cooking (with wine), walking her dog, reading, and recently joined a yoga studio!

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