This disease is caused by a protozoan of the giardia species.
Most infections in adult dogs are sub-clinical. Young dogs can develop a diarrhea syndrome characterized by the passage of large volumes of foul-smelling, watery (or "cow pie") stools. Diarrhea may be acute or chronic, intermittent or persistent, and may be accompanied by weight loss.
Dogs acquire the infection by drinking water from streams and other sources that are contaminated with infective oocysts.
Diagnosis is made by finding the protozoan or its characteristic oocysys in saline smears of fresh stool. Smears from rectal swabs are satisfactory. A negative smear does not exclude giardia, as oocysys are shed only intermittently.
Three negative rectal smears collected at least two days apart should be obtained before the diagnosis is excluded. Serology tests (ELISA, IFA) are now available.
Giardiasis responds well to Flagyl (metronidazole). Because Flagyl causes developmental malformations in the fetus, it should not be administered to pregnant females. Other effective drugs are available. There is now a vaccine available for giardiasis, but this is rarely recommended because the disease is usually mild and responds well to treatment.
Prevent your dog from drinking unclean water.
Please contact your veterinarian if you suspect your pet may be infected with this condition.
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