Lecture Quiz 11/10/15 Flashcards Preview

Parasitology 376 > Lecture Quiz 11/10/15 > Flashcards

Flashcards in Lecture Quiz 11/10/15 Deck (80):
1

What are the 3 phases of the apicomplexan life cycle?

  1. Infectious phase
  2. Proliferative phase
  3. Sexual reproduction phase

2

In which of the 3 life cycle phases does sporogony occur?

Infectious phase

3

What is the product of sporogony in the infectious phase?

Sporozoites

4

In which of the 3 life cycle phases does gametogony occur?

Sexual reproduction phase

5

In which of the 3 life cycle phases does merogony (schizogony) occur?

Proliferative phase (asexual)

6

Which of the following are enteric only?

Isospora

Toxoplasma

Neospora

Sarcocystis

Cryptosporidium

Eimeria

Eimeria

Isospora

Cryptosporidium

7

Which of the following are enteric and exterintestinal?

Isopsora 

Toxoplasma

Neospora

Sarcocystis

Cryptosporidium

Eimeria

Toxoplasma

Neospora

Sarcocystis

8

What do you call an infection with Eimeria?

Coccidiosis 

9

Which age of animals are more commonly affected by Eimeria?

Younger animals

10

ALL Eimeria are obligate intracellular parasites.  Where, specifically, are they usually found?

Gut epithelial cells AND/OR lacteal endothelium

Others: Kidneys; bile duct

11

Which species develop clinical signs to Eimeria?

Cattle

Sheep

Goats

Poultry

Rabbits

Camelids

12

The micropyle cap and micropyle are present in the oocyst of which species?

Q image thumb

Eimeria

13

Eimeria has a direct life cycle; how is it transmitted?

14

What is the infective stage of Eimeria?

Sporulated oocyst

15

What is the life cycle of Eimeria as it develops into the infective stage?

A non-sporulated, non-infective oocyst is shed in the feces --> containing a single-celled sporont --> oocyts must undergo sporulation (sporogony) to become infective

16

Sporont --> ______ --> sporocyst --> ______

Sporont --> sporoblast --> sporocyst --> sporozoite

17

How many sporoblasts originate from one Eimeria sporont?

4

18

Explain the process for an Eimeria sporont developing into sporoblasts

1 sporont

2 sporozoites

4 sporoblasts

19

In Eimeria, how many sporozoites are there per sporocyst?

2

20

All Eimeria species sporulated oocysts contain :

____ # sporocysts with ____ # sporozoites each

_____ # sporozoites per oocytst

All Eimeria species sporulated oocysts contain :

4 sporocysts with sprozoites each

=

sporozoites per oocyst

21

For Eimeria, where does sporogony occur?

In the environment

22

What are the environmental requirements of Eimeria sporogony?

Adequate moisture

Adequate oxygen

Adequate temperature 

 

23

True or False:

  1. Sporogony in Eimeria species can occur over a range of temperatures.
  2. Sprogony occurs more rapidly in warmer temperature.
  3. More oocysts become infective in the fall.

  1. TRUE
  2. TRUE
  3. FALSE - More oocyts become infective in SUMMER

24

Species?

Q image thumb

Eimeria

25

Merogony is synonymous to what other term?

Schizogony

26

Once in the host cell, the Eimeria sporozoite becomes what?

Meront

27

What term is synonymous to meront?

Schizont

28

The Eimeria meront (schizont) divides by multiple fission and produces what?

Many 1st generation merozoites

29

Merozoites of the final asexual generation proceed to what?

Gametogony 

30

What type of reproduction is gametogony?

Sexual

31

True or False:

The trophozoite stage of Eimeria is not infective.

TRUE

32

Eimeria female gametes:

One merozoite --> one _____ --> one _____

One merozoite --> one macrogametocyte --> one macrogamete

33

Eimeria male gametes:

One merozoite --> one _____ --> MANY _____

One merozoite -> one microgametocyte --> MANY microgametes

34

True or False:

  1. Microgametes remain in host cells.
  2. Macrogametes exit host cells in search of a microgamete.

  1. FALSE - microgametes exit host cells in search of a macrogamete.
  2. FALSE - macrogametes remain in host cells.

35

After the microgamete fertilizes a macrogamete in the host cell, what develops?

Zygote

36

What does the zygote become?

Zygote becomes sporont within oocyst

37

Which Eimeria life stage is represented?

Q image thumb

Microgamete

38

True or Flase:

Eimeria is unspecific to hosts.

FALSE

Each species is VERY host specific.

Ex: A calf is infected with E. zuernii and develops immunity to E. zuernii.  That calf is still susceptible to the other 14 Eimeria species that infect cattle.

39

Clinical disease associated with Eimeria is based on 3 things, what are they?

  1. Eimeria species involved
  2. Number of oocysts ingetsed
  3. Host factors (age, immune status, nutrition)

40

What are the clinical signs associated with an Eimeria infection?

Enteritis

Anorexia

Decreased feed efficiency

Weight loss

Diarrhea (mucoid to bloody)

Dehydration

Anemia 

41

Clinical parasitism with Eimeria in cattle (bovine coccidiosis) is most often seen at what age?

Calves less than or equal to 6 months old

42

What are the 3 clinical syndromes of bovine coccidiosis?

Enteric

Winter

Nervous

43

What clinical signs might be associated with Eimeria: bovine nervous coccidiosis?

CNS signs

GI signs

Muscle tremors

Staggers (nystagmus, convulsions, opisthotonos, +/- blindness)

44

Explain the mortality rate of Eimeria: bovine nervous coccidiosis.

High mortality rate with OR without treatment

45

For bovine Eimeria coccidiosis, where might you find lesions associated with asexual replication?

Distal ileum

46

For bovine Eimeria coccidiosis, where might you find lesions associated with sexual reproduction of the organism?

Cecum

Colon

47

Provide some prevention and control options for cattle farmers dealing with an Eimeria coccidiosis

Minimize overcrowding

Improve nutrition

Improve sanitation

Keep feces out of food/water supplies

Kill oocysts (sunlight, dessication)

Chemical disinfectants 

 

48

What is the OBJECTIVE when dealing with / controlling an infection with Eimeria in cattle?

Allow limited exposure to the parasite to stimulate immunity without developing CLINICAL DISEASE

49

How might Isosporus be transmitted?

  1. Fecal-oral transmission
  2. Paratenic host

50

What is the infective stage of isospora?

Sporulated oocyst

51

For Isospora, a rodent ingests a sporulated oocyst.

What is then released in the GI tract?

Sporozoite

52

Where do the sporozoites go once released in the GIT?

Penetrate the gut wall

Enter extra-intestinal cells

53

What does the sporozoite then form in the tissues?

Monozoic cyst

54

When the definitive ingests the rodent, what does the monozoic cyst release?

Sporozoite

55

Once the sporozoite for Isospora is released from the monozoic cyst in the intestine of the definitive host, what process is initiated?

Merogony

56

In summary, now explain the complete pathogenesis of Isospora infection from a paratenic host.

* Rodent ingests sporulated oocyst *

Sporozoites are released in the GI tract

Sporozoites penetrate the gut wall

Sporozoites enter extra-intestinal cells

Each sporozoite form a monozoic cyst

* Definitve host ingests rodent *

Sporozoite released from monozoic cyst

This initiates merogony in the intestine of the dog or cat

57

  1. For cystoisospora, what stage is shed in the feces?
  2. Where does sporogony occur?
  3. Where does merogony occur?
  4. Where does gametogony occur?

  1. Unsporulated cysts shed in feces
  2. Sporogony in environemtn
  3. Merogony in small intestine
  4. Gametogony in small intestine 

58

True or False:

Cystoisospora is usually non-pathogenic to mildly pathogenic.

TRUE

59

True or False:

Oocyst shedding of Isospora occurs right before clinical signs develop.

FALSE

Clinical signs precede oocyst shedding

60

Oragnism?

Q image thumb

Isospora

61

Complete the chart:

Q image thumb

A image thumb
62

What is the name of the Isospora that infects swine?

Cystoisospora suis

63

What specific disease does Cystoisospora suis cause in swine?

Neonatal porcine coccidiosis (NPC)

64

What is one characteristic known about the transmission of Cystoisospora suis?

NO paratenic host known

65

At what age does Cystoisospora suis typically affect pigs?

7-10 days of age

66

True or False:

  1. Cystoisospora suis in affected pigs can easily be treated with antibiotics.
  2. Cystoisospora is more prevalent in the humid periods of summer.

  1. FALSE - affected pigs are NON-RESPONSIVE to antibiotics
  2. TRUE

67

In post-mortem examination of a Cystoisospora suis case, where in the body would you look for gross lesions?

Jejunum

Ileum

68

On post-mortem examination of Cystoisospora suis, what changes would you see in histology of the jejunum and ileum?

Villus atrophy 

+

Parasites

69

What is the main mode of control of ALL coccidia?

SANITATION

70

Cryptosporidium is divisible into 2 groups based on location.

What are those 2 locations?

Stomach

Intestines

71

Which species of Cryptosporidium is probably the main zoonotic species/subspecies affecting immunocompetent people?

Cryptosporidium parvum (genotype II)

72

In what species can you find Cryptosporidium parvum genotype II?

Cattle

73

Which Cryptosporidium species is most commonly found in humans?

Cryptosporidium hominis

( parvum genotype I )

74

Which species of Cryptosporidia infect dogs and cats, respectively, and are considered zoonotic?

Cryptosporidium canis - Dogs

Cryptosporidium felis - Cats

75

Which organism differs from other Apicomplexans and develops in the enterocyte microvillus border, not in the cytoplasm of host cells?

Cryptosporidium parvum

76

As for Cryptosporidium, where does sporogony occur?

WITHIN THE HOST

Different from others we've talked about!!!!!!

77

  1. Which organism produces 2 types of oocytes?
  2. What are those types?

  1. Cryptosporidium parvum
  2. Thick-shelled  &  Thin-shelled

78

What is the difference between the thick-shelled oocyst of Cryptosporidium parvum and the thin-shelled oocyst?

Thick-shelled --> Passed in feces --> New host

Thin-shelled --> Can cause autoinfection

79

In which condition will calves recover as local immunity develops and is considered to be "self-limiting"?

Enteric cryptosporidiosis

80