Giardia are protozoans, tiny, one-celled parasitic life forms that can cause severe illness in dogs. These microorganisms cause giardia infection in the dog’s digestive system, which is called Giardiasis. Like many other parasitic infections, this infection is also characterized by microorganisms infiltrating the dog’s systems in order to survive. The dog gets infected by this infection by eating the cyst form (inactive form) of this parasite which commonly resides in the contaminated water and feces. Once ingested, the cyst opens in the intestine and releases its active form called trophozoite, which has flagella, hair-like structures that whip back and forth enabling them to move around. Trophozoite attaches itself to the intestinal wall and reproduce by dividing in two. After an unknown number of divisions, at an unknown location, this form grows a wall around itself called encysts, which gets passed through the feces. If the dog is healthy i.e. has a strong immune system, the trophozoites may survive in the lower digestive tract for a few years. But if the dog has a weak or overburdened immune system, the trophozoites may thrive well and will continue to multiply by dividing and will eventually cause this debilitating disease. Hence, giardia in the dog’s feces contaminate the environment and water, which can even lead to infections in other animals and in humans too.
Symptoms of Giardia in Dogs
During the initial stages, Giardia symptoms are not detected as most of the time, the parasites penetrate into the dog’s body and remain inactive in the intestine for long periods of time. In fact, sometimes it takes really long to detect their presence even after their activation period has started.
Vomiting: Vomiting is the first observable symptom that can be seen in the infected dog. Frequent vomiting with some other gastointestinal problems are also diagnosed in the dog having giardiasis.
Fever: The infected dog may suffer fever that may persist for three or four days. In some cases, the dog may have recurring fever that may proceed into an increasingly sub-acute phase.
Loss of Appetite: Most of the infected dogs slowly lose interest in the food. This begins gradually, with the dog eating smaller quantities during the meals and eventually stops eating altogether.
Weight Loss: Due to poor eating habits, over a period of time the dog will exhibit substantial weight loss. Besides this, one can also observe secondary symptoms like malnutrition, lack of energy, and loss of fur.
Diarrhea: Of all other giardia in dogs symptoms, canine diarrhea is the most evident one. The feces of the sick dog will be watery, grease-like and highly pungent in odor. In some cases, the feces can also be accompanied by visible mucous deposits due to inadequate absorption of food.
Diagnosis of Giardia in Dogs
Giardiasis in dogs is difficult to diagnose since the protozoa are too small and are not passed with every stool. Therefore, series of stool samples (one stool sample each for three consecutive days) are usually required to detect the micro organism. Direct microscopic inspection of feces or fecal flotation test is done to detect the presence of the cysts and active trophozoites in them. Cysts are commonly found in firm stools, hence special solutions are used to separate and examine them microscopically. Nowadays, an advanced diagnostic test using ELISA technology is employed to have an accurate fecal examination. The test uses a very small fecal sample and can be performed within 8 minutes in a veterinarian’s clinic.
Treatment for Giardia in Dogs
Conventional treatment for giardia in dogs uses medications like Metronidazole (Flagyl), Fenbendazole, Albendazole, and Quanacrine. Metronidazole (Flagyl) is an old stand-by treatment for bacterial infestations that leads to diarrhea in dogs and is highly effective in curing giardiasis. However, it has some side effects including vomiting, anorexia, liver toxicity, and is teratogenic, i.e. can cause physical defects in embroys, hence can’t be given to pregnant animals. Fenbendazole has less side effects than Metronidazole and is also effective in treating canine giardia. Albendazole and Quanacrine are other two medications that help curing giardia in dogs but can cause anorexia, lethargy, and fever in them.
Besides these conventional medications, there are various natural remedies that can help overcome the symptoms, like grapefruit seed extract capsules or herbs like oregon grape and goldenseal. Since, giardia can also infect human beings, keeping the kennel and exercise areas clean, washing hands after cleaning dog runs or removing feces from yards are some preventive measures, that should be taken into consideration to avoid such health ailments.