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Flashcards in Protists Deck (75):
0

In what animal and organ is Klossiella normally found

In the kidneys of horses and mice, usually nonpathogenic

1

Which species of Cyclospora is found in humans
What clinical signs are associated

C. cayetanensis
Diarrhea in people in South America

2

What are some hosts of Cyclospora

Snakes, primates, rodents, insectivores (and moles)

3

How is Cyclospora usually transmitted to people?

Ingest contaminated water or produce (raspberries!!!)

4

Define some terms relative to the life cycle of Protista.
Zoite
Sporozoite
Tropozoite
Schizigomy
Gametogeny
Zygote

Zoite - motile form
Sporozoite - haploid stage
Zygote - diploid stage
Tropozoite - stage once the protist has entered a cell
Schizogony - split asexually (schizizoites are daughter cells of this split)
Gametogeny - sexual reproduction

5

For Cystoisospora, what stage does the life cycle arrest at

Arrested sporozoite stage

6

Characterize the oocyst of Cystoisospora

No polar cap
2 sporocysts each with 4 sporozoites in them

7

What is the prevalence of Cystoisospora in regards to age ranges

More prevalent diseases in young animals

8

What part of the animal do Sarcosysts live in?

Muscle

9

What are key features of the Sarcocystis life cycle

Requires a vertebrate intermediate host where schizonts develop in the endothelial cells, then sporulated sporocysts form oocysts that are seen in the muscles
Carnivorous final host where gametogony only occurs in the intestinal cells

10

Why is EPM only seen in the Americas

The intermediate host is the the opossum... Only 4 species, in Americas
Sheds sporocysts into environment

11

What is EPM and what organism causes it?

Equine protozoal myeloencephalitis
Sarcocystis neurona

12

What is one characteristic of EPM infection?

Formation of schizonts in dividing cells in equine (neural) tissues
Cats, skunks, & 9 banded armadillos can have muscle stages

13

What role do cattle serve in the Besnoitia besnoiti life cycle

Intermediate hosts

14

What is the final host of most Besnoitia species of veterinary significance

Cats

15

What are the intermediate hosts of 2 species of Besnoitia besides B. Besnoiti

B. Darlingi - opossums in US
B. Wallacei - rodents in US

Other B. Species affect donkeys, mainly miniature donkeys

16

What does a facultative heteroxenous life cycle refer to?
Ex. Of one organism that has this type of life cycle.

Can utilize paratenic hosts... Can be completed in a single host or can utilize other hosts for completion of the life cycle

Toxoplasma

17

In what animal was Toxoplasma gondii first found

A gundi, a small rodent in North Africa

18

Which life stage of people are most severely affected by Toxoplasma and which life stage of the agent is responsible for disease?

Newborn infants infected in utero
Tachyzoite

19

What form of Toxoplasma gondii is shed in cat feces

Oocysts

20

How are people infected with Toxoplasma gondii

Ingest raw/undercooked meat (visceral infection with small cysts in paratenic hosts; with the general exception of beef) or oocysts from contaminated soil or vegetables (enteric infection in cats, shed in feces).

21

What are the 4 forms that toxoplasma gondii appears as in human hosts

1. Chronic infxn with bradyzoites
2. Acute disease with multiplying tachyzoites following first exposure
3. Infection of infants in utero
4. Recrudescence by reactivation of Brady into tachyzoites

22

What needs to happen for recrudescence of an existing infection to occur?

Immunosupression

23

When is a fetus in danger of being infected with toxoplasma

When the mother is infected for the very first time while pregnant

24

Why are signs worse when the fetus is infected during the first trimester

More cells are rapidly dividing

25

What species of Protista is normally associated with posterior flaccid paralysis in puppies

Neospora caninum

26

How are most puppies with Neospora caninum derived paralysis infected

Transplacentally

27

What other species are affected by Neospora caninum, and how

Cow, causes abortions. Usually no repeat abortions.

28

What are vectors of hepatozoon of different species

Hepatozoon canis and Hepatozoon americanum in dogs transmitted by tick... Rhipicephalus sanguineus and Amblyomma maculatum respectively
Species in rodents vectored by mites
Species in reptiles vectored by mosquitoes

29

Describe the life cycle of Hepatozoon americanum in reference to its hosts

Ingested by tick as gamonts in blood,
sexual replication in tick gut makes oocysts in body cavity of tick,
Dog eats tick or paratenic host (infected rabbit)
Schizonts occur in various tissues and gamonts in white blood cells

30

What clinical signs are associated with Hepatozoon infection in dogs
How is it treated

Arthritis pain
Relapses are expected
No real Tx, control with quinolone anticoccidial agent

31

What is the only vertebrate host cell affected by Babesia

Red blood cells

32

What species causes bovine piroplasmosis

Babesia bigemina, often gather in pairs to destroy RBCs

33

How is Babesia bigemina transmitted

Rhipicephalus ssp.

34

How is Babesia transmitted from tick to tick

Vertically, sporozoites multiply in the tick ovary infecting larva that hatch from her eggs

35

What is the vector of Babesia divergans and why is it important

Ixodes ricinus - it is a 3 host tick and the parasite is transmitted to all three stages. Humans can be affected *zoonotic*

36

What species of Babesia affect dogs and what are their intermediate hosts
What are signs associated with disease

Babesia canis and Babesia gibsoni
Rhipicephalus sanguineus and Haemaphysalis longicornis, H. bispinosa

Hematuria and jaundice

37

How is Theileria is different from Babesia in infection of cells

Theileria infects lymphocyte and schizonts in lymphocytes induce them to undergo proliferation and division

38

How is Theileria transmitted and what is the associated disease

Via tick bite
East coast fever in cattle (enlarged lymph nodes) and deer - affects erythrocytes, lymphocytes and endothelial cells

39

What agent and vector are associated with equine piroplasmosis

Theileria equi
Amblyomma cajennense

40

What do people infected by Babesia and Theileria often have in common

Been splenectomized

41

How does Cytauxzoon differ from Theileria?

Schizonts in vertebrates occur in macrophages instead of lymphocytes

42

How does Cytauxzoon kill cats

Turn blood into macrophage jelly, occlude the lumen, no room for RBCs in lungs spleen and LNs

43

What is the natural host of Cytauxzoon felis

Bobcat, Lynx rufus

44

What is the vector of Cytauxzoon felis to cats

Amblyomma americanum

45

What is the best way to prevent a cat's infection with Cytauxzoon

Seresto collar

46

What is the causative agent of malaria

Plasmodium

47

What species can be affected with malaria

All primates, birds, rodents, and reptiles (mainly lizards)

48

Brief overview of life history of plasmodium

Sporozoites injected into host during mosquito feeding
Enter hepatocytes and become trophozoites, then undergo schizogony, cell lysis merozoites enter RBCs and undergo second round of schizogony. Cycle continues with RBCs
Eventually merozoites develop into gametocytes and are ingested by mosquito. Within mosquito they mature and develop fertilized zygotes.

49

How does the life cycle of plasmodium manifest as clinical signs

Cycles of schizogony manifest of cycles chills (schizogony within cells) and fever (cells rupture and release merozoites)

50

Haemoproteus are parasites of what animals
Associated disease?

Birds, turtles and lizards
Considered nonpathogenic

51

What are vectors of Haemoproteus

Culicoides, hippoboscidae, chrysops - ingest erythrocytes containing gametocytes

52

What are Leucocytozoon parasites of

Domestic and wild birds

53

What are vectors of Leucocytozoon

Black flies (simulium)

54

Which species develops megaloschizonts in the liver of chickens

Leucocytozoon caulleryi

55

Which species are parasitized by Hepatocystis?

Lower monkey, fruit bat and old world squirrels

56

Give examples of photosynthetic Stramenopiles

Brown seaweed, diatoms

57

Give an example of non photosynthetic Stramenopiles

Opalinids - small group of amphibian parasites
Saprolegniales - water molds

58

What is the common name for Saprolegniales

Water molds

59

How do water molds get their energy

Saprophytic - feed on dead things
Weakly parasitic

60

How do water molds reproduce

Asexual - sporangia (structures containing spores) release zoospores (motile asexual spore that uses a flagellum for locomotion)
Sexual - gametangial contact

61

Name one disease caused by water molds bad the animals severely affected

Pythiosis
Dogs and horses

62

What are the three parts of brown algae

Root-like holdfast, stem-like stipe, and a leaf-like blade

63

What is the host of Blastocystis hominis

Humans and a wide range of animals (birds, mammals, reptiles, amphibians and arthropods)

64

Does water treatment kill 100% of Blastocystis?

No, Blastocystis populations remain high in sewage

65

What type of organisms make up the classification of Excavates

Amoebas

66

What is the cause of primary amebic meningoencephalitis

Naegleria fowleri

67

How is Entamoeba histolytica transmitted

Human to human via feces

68

What is a diagnostic histological legion of Entamoeba histolytica

Upside-down champagne glass shaped lesions in intestinal mucosa

69

What is unique about Entamoeba histolytica

They (only amoebas to) eat red blood cells

70

What is nonpathogenic amoeba that is morphologically indistinguishable from Entamoeba histolytica

Entamoeba dispar

71

How does Acanthamoeba typically infect people

Dirty contact lenses, causing eye disease (keratitis)

72

How is Acanthamoebic keratitis often misdiagnoses

As herpes simplex virus infection

73

What is disease progression to Acanthamoebic encephalitis

Inefection in skin, hematogenous spread to the brain of immunosuppressed individuals

74

What is another organism besides Acanthamoeba that can cause granulomatous amebic encephalitis

Balamuthia, also usually involves skin lesions and associated with a finger stick.