Symptoms of Toxoplasmosis in Dogs

Toxoplasmosis is a parasitic disease affecting humans, dogs and cats. Dogs generally contract the Toxoplasma gondii parasite by ingesting raw meats or vegetables, eating dead rodents or birds, ingesting the feces of an infected cat, drinking unpasteurized goat's milk or drinking contaminated water. A pregnant dog that contracts the parasite will pass it on to her unborn puppies.

If outdoor cats use your food garden as a litter box, the protozoa can spread to vegetables. Should your dog enjoy raw vegetables, it's easy for the parasite to enter the dog's digestive system. Thoroughly washing all vegetables before serving to your dog is important.

Some dogs infected with Toxoplasmosis never show any symptoms. However, other dogs may develop symptoms affecting the nervous system, respiratory system or vision. The disease is a higher risk in dogs with conditions that reduce immunities.

How Toxoplasma Gondii Develop

In the first stage of a Toxoplasma gondii's life, the sexual stage, the protozoa require a feline host. The feline host eats an infected rodent or bird. The parasites enter cells in the intestines and reproduce. Eventually, they exit through the feces where they move onto the next stage of life.

The second stage of life, their asexual stage, doesn't require a feline host. Any warm-blooded mammal will suffice. They enter the bloodstream from the intestines and travel to other areas of the body, particularly the brain and lungs. The immune system of a dog usually fights the protozoa at this point. In some dogs, especially puppies and dogs with poor immune system function, the disease will cause other health issues. Still, six out of ten animals respond quickly to antibiotic treatments.

Toxoplasmosis Symptoms Affecting the Central Nervous System

The Toxoplasma gondii organism may cause problems with brain function. Common complaints include:

  • Cardiac arrhythmia

  • Depression

  • Impaired nerve function

  • Loss of muscle control causing the head to tilt to one side

  • Paralysis

  • Seizures

As these symptoms are linked to other illnesses, it's important to have your dog checked by a veterinarian. Blood tests can help diagnose the illness allowing your pet to receive necessary antibiotic treatments to cure the disease.

Respiratory Symptoms Caused by Toxoplasma Gondii

Toxoplasma gondii frequently gather in the lungs. This causes a number of respiratory complaints, including:

  • Coughing

  • Increased breathing rate

  • Labored breathing

  • Pneumonia

Toxoplasmosis Symptoms Affecting Vision

In the eyes, Toxoplasma gondii cause inflammation. As a result, the dog may blink rapidly and become extremely sensitive to bright lights. He may squint when looking at things in an attempt to shade the eyes from light.

In conjunction with the nervous system, partial to complete blindness may occur. The dog may suddenly be unable to see anything and begin walking into objects in and outside the home.

Other Symptoms Linked to the Toxoplasma Gondii Organism

There are other symptoms not directly tied to the nervous system, eyes or brain. If the parasite attacks the liver, inflammation will cause the liver to enlarge. As a result, jaundice may set in.

Dogs with Toxoplasma gondii may lack any appetite and start to lose weight. Fluid can start building up in the abdomen causing swelling. Muscle pain and fever, much like a case of the flu, is also a possibility.