4. Morphology of Giardia lamblia trophozoite Each trophozoite has ____________________ (looks like monkey face) Ventral surface bears _______________________ to adhere to surface of intestinal cell 8 flagella (2 anterior, 2 posterior, 2 ventral, and 2 caudal) - all arise from ________________________ ________________________ occur behind adhesive disk - function is unknown

5. Morphology of Giardia lamblia trophozoite Scanning EM view of trophozoite surface showing the adhesive disk (text photo on p. 92) ventral dorsal

6. Morphology of Giardia lamblia trophozoite Light microscope photos of trophozoites

7. Morphology of Giardia lamblia trophozoite Trophozoite attaches to surface of epithelial cells with its adhesive disk and feeds on _____________________________________________

9. 2 nd Stage is Giardia lamblia cyst

10. Giardia lamblia life cycle DIAGNOSIS ? INFECTIVE STAGE? PRIMARY DIAGNOSTIC STAGE?

15. Other species of Giardia 5 species of Giardia occur in other birds and mammals; They are not thought to be transmissable to humans Giardia muris Giardia canis Giardia felis Giardia equi

18. Chilomastix mesnili life cycle stages 2. CYST is lemon-shaped; 6 to 10 µm in diameter - anterior end: __________________ - contains single nucleus, cytosome, and retracted flagella - common diagnostic stage in feces

19. Chilomastix mesnili life cycle 1. Trophozoites live in the human large intestine and multipy by _____________________________ 2. ___________________________ in the large intestine stimulates encystment. Cyst is released in the feces. 3. Cyst survives in water in the external environment. 4. When cyst is ingested, it excysts in the small intestine and moves to the large intestine. Transmission involves ingestion of cysts primarily from _____________________________ contaminated with feces.

20. Chilomastix mesnili life cycle PATHOLOGY: IMPORTANCE:

22. General Morphology of the Trichomonas trophozoite Shape: Nucleus: 3 to 5 flagella extend anteriorly 1 flagellum extends posteriorly along the cell membrane to form an _______________________________ _______________________________attaches the undulating membrane to the cell membrane and gives the undulating membrane support

23. General Morphology of the Trichomonas trophozoite Internal support provided by: _______________________________ is a Golgi apparatus located near the nucleus (not generally seen in most specimens)

24. 3 species of Trichomonas occur in humans

26. Trichomonas hominis = Pentatrichomonas hominis Host and habitat: Pathology: Food:

27. Trichomonas hominis = Pentatrichomonas hominis Trophozoite is usually between 8-12 µm in length ID characters: Often is placed in genus Pentatrichomonas due to presence of 5 anterior flagella Undulating membrane and 6th flagellum runs length of parasite but are not seen in most smears

28. Life Cycle of Trichomonas hominis 1. Trophozoites live in the human large intestine and multipy by binary fission . 2. Dehydration of the feces in the large intestine caused the trophozoite to round up and become dormant. No cyst is formed. 3. Trophozoites are released in the feces and survive in water in the external environment. 4. When trophozoite is ingested, it passes down the digestive tract to the large intestine.

29. Life Cycle of Trichomonas hominis PATHOLOGY: IMPORTANCE:

30. Trichomonas vaginalis Host and habitat: Food: Common in 30-49 year old women; a recent study in California indicated a prevalence of 30% in childbearing women

31. Trichomonas vaginalis Morphology: Size: ID characters: - all structures show in stained specimens

32. Life Cycle of Trichomonas vaginalis 1. Trophozoites occur in the urogenital system. 2. Trophozoites multiply by binary fission. 3. Trophozoites are transmitted from one person to another by ____________________________________________________________________________________ (washcloths, towels, etc.). Fomites

33. Pathology of Trichomonas vaginalis infections Pathology in men: ________________________________ _______________________________________________ Pathology in women – causes _________________ infection: (1) (2) (3) These symptoms disappear in women as the infection becomes chronic; she becomes asymptomatic. Parasite is often sexually transmitted from an asymptomatic person to his/her partner.

35. Two non-human species of Trichomonas Trichomonas (=Tritrichomonas) foetus Parasite of veterinary importance in _____________________________ Habitat: PATHOLOGY in cows: PATHOLOGY in bulls: Treatment is expensive and not always effective

36. Two non-human species of Trichomonas Trichomonas muris - common parasite in _____________________________________ - nonpathogenic - occur in uncountable numbers

37. Dientamoeba fragilis Parasite was originally thought to be an ameba but recent EM and immunological studies indicate it is more closely related to Trichomonas HABITAT - ___________________________________________________ - it is cosmopolitan and infects 4% of the world's population

38. Dientamoeba fragilis MORPHOLOGY - Trophozoite is round in shape - 6 to 12 µm in diameter - nucleus: cyst?

39. Dientamoeba fragilis LIFE CYCLE - parasite does not form cysts and trophozoites cannot survive passage through the small intestine TRANSMISSION: Transmission through eggs of pinworm and whipworm

42. Histomonas meleagridis life cycle Transmission is within the egg of the cecal nematode of chickens and turkeys ( Heterakis gallinarum ) - trophozoites from the cecum of an infected bird are ingested by the nematode and invade the eggs - infected eggs of the nematode are released onto the soil where they are eaten by young birds during pecking activities - as nematode eggs hatch in small intestine, Histomonas trophozoites are released to invade cecum and liver

43. Histomonas meleagridis pathology Habitat of trophozoites: Pathology: Young turkeys are more susceptible to the infection than are chickens Mortality can reach 100% in young turkeys - millions of dollars worth of turkeys are lost to this parasite

44. Termite Flagellates Trichonympha and Holomastigotes are common genera inhabiting the intestine of termites. This is an example of ___________________________ Trichonympha Holomastigotes

48. Balantidium coli life cycle 1. Trophozoites live in the human large intestine and multipy by binary fission . Conjugation may occur but it is rare. 2. Dehydration of the feces in the large intestine stimulates encystment. Cyst is released in the feces. 3. Cyst survives in water in the external environment. 4. When cyst is ingested, it excysts in the small intestine and trophozoite moves to the large intestine.

49. Balantidium coli Pathology Trophozoites are tissue invaders. They secrete proteolytic enzymes which digest the epithelium of the large intestine. __________________________________ are formed in the mucosa of the large intestine and extend into the submucosa. Ulceration results in bleeding and secondary bacterial infection. Perforation of the large intestine has occurred in some fatal cases. Disease is primarily _________________ _________________________________ Secondary infections in other organs such as liver and lungs are rare.

50. Balantidium coli TREATMENT: PREVENTION:

52. Ichthyopthirius multifiliis Trophozoites are released into water when skin pustules rupture Cysts are formed and _____________________________occurs within the cyst Trophozoites are formed and are infective to a new fish when it comes into contact

53. Ichthyopthirius multifiliis Treatment: