Scooping feces is part of being a pet owner, but knowing what your pet’s feces may contain is also an important part of pet ownership. Our Town & Country Animal Hospital team explains the Giardia parasite that could be lurking in your dog’s feces, and shares important information you need to know to keep you and your furry pal safe and healthy.

#1: Giardia is an intestinal parasite

Although Giardia is an exceptionally tiny single-celled organism, this intestinal parasite can cause a great deal of gastrointestinal (GI) distress for affected dogs, cats, livestock, wildlife, and people. Its pear-shaped, flagellated form allows the parasite to efficiently swim and attach to the animal’s intestinal lining and leach nutrients and cause inflammation.

#2: Many different Giardia strains exist

The various Giardia strains allow it to infect many different species, ranging from domestic pets, to ruminant livestock, to people.

#3: People generally cannot get Giardia from their pet

While many parasites can be transmitted from pets to people via contaminated water, dirt, food, or feces, pets rarely give Giardia to people. The Giardia strains that infect dogs or cats tend to stay in their own species, so you or your cat are unlikely to contract Giardia from your dog.

#4: Your dog can get Giardia from multiple sources

In its cyst form, Giardia is highly infectious and your dog can easily be infected from multiple sources. Some ways in which your dog can contract Giardia include:

  • Drinking contaminated water — Stagnant water sources, like puddles and ponds, can contain Giardia cysts that can infect your dog when they drink.
  • Dirty environments — As your dog walks across a dirty floor in a pet store or contaminated soil in a dog park, they can pick up cysts on their paws. Then, when they lick their paws, they ingest the cysts and become infected.
  • Contact with infected dogs — Your dog can become infected through accidental cyst ingestion when they groom, greet, or play with an infected dog.

#5: Giardiasis results in particularly foul-smelling stool

One of the hallmark giardiasis signs is foul-smelling stool. Your dog’s feces can appear greasy, contain mucous, and be passed as a soft, pale pile of loose stool. The stool rarely contains blood, despite Giardia’s propensity to attach to intestinal walls.

Additional giardiasis signs in dogs include:

  • Abdominal discomfort
  • Excessive gas
  • Poor coat condition
  • Lethargy
  • Decreased appetite
  • Weight loss
  • Vomiting

While giardiasis can cause serious illness in affected dogs, many dogs are asymptomatic, with a normal appetite and energy levels. Pets may also have intermittent diarrhea that appears to resolve, only to suddenly occur again.

#6: Giardia can be difficult to diagnose

Giardia cysts are not always shed in the stool, so a single sample may give a false negative result. To accurately diagnose giardiasis in dogs, a history of your dog’s clinical signs and lifestyle will be taken into account along with their physical exam findings. Then, two types of fecal tests will be performed: 

  • Standard — A standard fecal test, which evaluates a stool sample for parasite eggs and Giardia cysts
  • Antigen — An antigen test to detect small proteins produced by the parasite

#7: Giardia treatment may not always be necessary

Many dogs do not develop clinical illness with giardiasis, and they may not need treatment, which generally is reserved for dogs with active diarrhea and other clinical signs.

#8: Bathing is an important part of a giardiasis treatment plan

Since Giardia cysts can cling to your dog’s fur after they defecate, a good bath is an important part of Giardia elimination. Reserve your pup’s spa day for the end of their antibiotic course, and then bathe them thoroughly to remove every trace of the parasite.

#9: Giardia is difficult to kill in the yard

Giardia cysts are exceptionally hardy, and can survive in the environment for months, especially during the winter.

#10: Dogs easily can reinfect themselves with Giardia

Since Giardia cysts are infectious immediately after they are shed, your dog can reinfect themselves unless you practice excellent hygiene. To prevent reinfection, encourage your dog to drink only clean water and avoid puddles, ponds, and other stagnant water. Always pick up your dog’s feces immediately, and stay away from piles left behind by other dogs. After your dog has finished their treatment course, use a new area in your yard as your dog’s bathroom, so the sun can bake the existing Giardia cysts, rendering them ineffective. Inside, disinfect every area where your dog rests and wash their bedding to destroy cysts.

Preventing intestinal parasite infections is an essential part of your dog’s overall wellness care plan. For help in learning how to prevent intestinal parasite infections, like giardiasis, in your four-legged friend, talk to our Town & Country Animal Hospital team.