Giardia is a protozoan flagellate which is found in the intestinal tract of human and animals. It is one of the most common parasites in dogs. The infection is clinically important due to its high prevalence, clinical symptoms - especially in puppies-, its difficulty in control and its zoonotic potential. Giardiasis can be transmitted by direct contact or by fomites. Cysts are passed from the host to the environment through feces. One particular condition of Giardia is that cysts are intermittently shed in the feces. Outside, cysts survive for months in moist conditions but are extremely susceptible to drying. This parasitosis occurs far more frequently in kennels or shelters since young animals and crowded environments constituted important risk factors. Protection against Giardia in kennels needs more complex measures than in household with individually kept dogs. In this report, it is presented two cases of giardiasis in kennels: The first one was a breeding kennel where puppies where clinically affected, showing diarrhea, weight loss and growth retardation; adult dogs were asymptomatic. The other one was a shelter, where most dogs were adults with chronic diarrhea. In some animals, feces were malodorous and steatorrheic. Faecal specimens were collected and were analised using zinc sulphate flotation/centrifugation technique. In some cases, at least three fecal fresh samples had to be examined due to intermittent shedding cysts. The main approaches to control giardiasis were focused on environmental decontamination and detection of carrier dogs. Environmental disinfection with quaternary ammonium, decrease environmental humidity, treatment of all animals - even asymptomatic since they may continue to shed cysts - with fenbendazole (50 mg/kg), fomites control and routinely coprological controls of all animals, especially those that were newly acquired or incoming dogs, constituted the main strategies followed up in both communities.

Acknowledgments: This study was partially financed by Servei de Salut Pública i Consum de la Diputació de Barcelona, Spain.