Exam III - Giardia intestinalis Flashcards
What is/are the host(s) for Giardia intestinalis?
Mammals
Which assemblage of Giardia intestinalis infects dairy cattle, but not humans
Assemblage E
Describe the appearance of the Giardia intestinalis trophozoite
~21 µm long, teardrop, 2 nuclei, 8 flagella, facelike appearance
Describe the appearance of the Giardia intestinalis cyst
12 µm long, ovoid, 4 nuclei
What is the infective stage for Giardia intestinalis?
cyst
Describe the Giardia intestinalis life cycle
Direct life cycle. One stage is a cyst, one stage is a trophozoite. Infective stage is a cyst.
Trophozoites stick to the microvilli of the small intestinal epithelial cells and multiply asexually. After several replications, a trophozoite encysts to form a cyst. Cysts pass down the small intestine, are passed in the feces, and are the infective form.
Trophozoites are not able to survive long outside the host, whereas cysts survive for 2-4 weeks. PPP is 1-2 weeks.
What is/are the site(s) of infection for Giardia intestinalis?
Small intestine
Describe any clinical signs associated with Giardia intestinalis
Acute or chronic diarrhea
Describe any pathogenesis associated with Giardia intestinalis
Many infections are asymptomatic. Trophozoites can cause acute focal inflammation
How would you diagnose Giardia intestinalis?
Detection of cysts in fresh fecal smear (If feces are really fresh, you may see some trophozoites).
Zinc sulphate floatation with Lugol’s iodine is ideal
Describe some important steps in prevention of Giardia intestinalis
Prevention of fecal contamination with water and feed is important, sanitation & disinfection of environment
Water filters with 10µm diameter will prevent transmission
Treatment options for Giardia intestinalis in cattle?
fenbendazole, albendazole, dimetridazole
What is the common name for Giardia intestinalis?
Beaver fever
