Parasitology - Protozoa 2

Front 1

Name 6 genera of Intestinal Apicomplexa

Back 1

1. Cryptosporidium
2. Eimeria
3. Isospora (Cystoisospora)
4. Neospora?
5. Toxoplasma
6. Sarcocystis?

Front 2

Monoxenous means?
Gve example of monoxenous parasite (in Intestinal Apicomplexa):

Back 2

1 host, host specific
The species usually strictly host specific, using only a single host species e.g. Eimeria and Isospora (Cystoisospora); but sometimes will infect other host undergoing only asexual reproduction?

Front 3

Eimeria has how many sporocysts? how many sporozoites in each sporocyst?

Back 3

4 beers each for 2 dollars

4 sporocysts each containing 2 sporozoites

(pic shows Eimera's reptilian isolet)

Front 4

Cystoisospora has how many sporozoites?

Back 4

2 sporocysts each containing 4 sporozoites

2 beers each for 4 dollars
Cystoisospora more expensive...

Front 5

T or F: Merozoites can contain thousands of Schizonts

Back 5

False: Formation of Schizonts (which contain thousands of merozoites)

Front 6

What protozoan parasite associated with BOVINE Coccidiosis?

Back 6

EIMERIA spp.
(E. bovis , E. zuernii )

Front 7

What are symptom of Winter Coccidiosis ?

Back 7

Bloody diarrhea, tenesmus (straining). Rectal prolapses may occur. Secondary bact. enteritis and pneumonia is common sequelae.

Front 8

Most common EIMERIA spp.

Back 8

E. bovis

Front 9

Worldwide distribution; estimated to cost > $70 million annually in production losses. Extending calving due to coccidiosis would cost $60-$70.

Back 9

E. zuernii

Front 10

Eimeria nonpathogenic in what animals?

Back 10

Nonpathogenic species in horses & pigs

Front 11

Eimeria Very important pathogen in what spp.?

Back 11

cattle & poultry industries.

Front 12

Eimeria clinical signs usually in calves of what age?

Back 12

usually appears in 4 wk-old calves

Front 13

What is the only species of enteric coccidia reported from N. American horses, oocysts very large with thick dark brown wall, appears to be prevalent and relatively harmless?

Back 13

only E. leukarti - mostly harmless, large oocysts

Front 14

What is the most important species involved in coccidiosis in pigs?

Back 14

I. suis

Front 15

What is the causative agent of avian coccidia, it is most severe in young chicks, causes enlarged inflammed cecae and bloody cecal contents, diarrhea, reduced weight gain and egg producction?

Back 15

E. tenelia

Front 16

If cow has recovered from Eimeria, can it be reinfected?

Back 16

No, unless immune suppressed e.g. via stress

Front 17

Lamma & alpacca Eimeria spp.?

Back 17

E. macusaniensis

Front 18

How do you diagnose coccidia?

Back 18

emonstration of oocysts on fecal flotation

Front 19

E. macusaniensis symptoms

Back 19

Severely affected animals had signs of lethargy, weight loss, anorexia and diarrhea. Also evidence of: circ. shock, protein loss, renal insuff., bile stasis and hepatic lipidosis

Front 20

In rabbits, Liver (E. stiedai) is more important than the intestinal

Back 20

True

Front 21

CYSTOISOSPORA have how many sporozoites?

Back 21

Sporulated oocysts have 2 sporocysts, each with 4 sporozoites.
(2 beers for 4 dollars

Front 22

Species of isospora in dogs

Back 22

Four species of Isospora in dogs
Isospora canis is the largest oocyst (36 X 30 µm). Isospora ohioensis, I. neorivolta, and I. burrowsi

Front 23

isospora found where in dog?:?

Back 23

All inhabit the small or large intestine

Front 24

Hypozoite – occur in __?

Back 24

Hypozoite – occur in tissues of paratenic hosts

Front 25

What is recommended for all calves aged less than 3 weeks of age and newborns, calves that recieved this were significantly less likely to shed cryptosporidium oocysts?

Back 25

halofuginone lactate (halocur)

Front 26

CYSTOISOSPORA TWO EXCEPTIONS

Back 26

1. extraintestinal stages (hypnozoite = 1 sporozoite) occur in the tissues of paratenic hosts (mice, rats, hamsters, opossum).
2. extraintestinal stages occur in the tissues of the dog, cat and humans (I. belli).

Front 27

how is life cycle of sarcocystis unique?

Back 27

asexual stage in intermediate host (prey) and sexual stage is in definitive host

Front 28

Neospora is taxonomically and genetically related to ?
What is more likely to cross placental barrier?

Back 28

Neospora caninum is easily mistaken for Toxoplasma;

but Neospora more likely to cross placental barrier

Front 29

What is the definitive host of Neospora caninum? What are the intermediate hosts? What is the most common host?

Back 29

Dogs are the definitive host of Neospora caninum. Intermediate hosts are herbivores, especially cows.

Front 30

Most of Neospora related abortions happen in what term?

Back 30

mid to late term abortions
(in bovine btw. 4-8 mo. of gestation)

Front 31

Which cows more likely to abort due Neospora infection?
A. asymptomatic cow with congenital infection
OR
B. cow infected by ingesting oocysts (horizontal transmission)

Back 31

A. Although may be asymptomatic with congenital infection, more like to abort!
~Somehow Neospora maintains low grade infection which becomes reactivated upon pregancy, crossing placental barrier with ease.

Front 32

Is Neospora zoonotic?

Back 32

unknown, although antibodies found against parasite, no parasite or clinical signs detected

Front 33

How might dog get Neospora infection horizontally (if not congenital infection)?

Back 33

Eating a placenta or aborted fetus of dairy cow

Front 34

What possible clinical signs / symptoms of Neospora in puppy? (3)

Back 34

CNS signs, dermatitis, pneumonia

Front 35

What possible clinical signs / symptoms of Neospora in older animal? (4)

Back 35

Older dogs
Neural, myocarditis, generalized disease, myositis, dermatitis

Dermal Neosporosis more common in older dogs, get ulcers

Front 36

Best way to diagnose neonate calf?

Back 36

Get serum, preferably pre-colostrum, before it has gotten antibodies from mother (check this)

Front 37

How might dairy cow get infected with Neoplasma horizontally (if not congenital infection)?

Back 37

Dogs can pass oocysts if defecate on hay etc, although do not shed a lot Neospora oocysts and difficult to detect

Front 38

What tissue of aborted fetus might look to detect Neospora cysts/tachyzoites?

Back 38

Brain, heart, occular musc. of eye, maybe liver
(NOT sk.muscle like Sarcocysta)

Front 39

Neospora caninum cysts are (smaller OR bigger) than T. gondii cysts?

Back 39

Neospora are smaller

Front 40

Equine protozoal myeloencephalitis is caused by what parasite? Sign include lameness, ataxia, excess sweating, and loss of reflex also occur.

Back 40

Sarcocystis neurona.

Front 41

Identify this parasite. Cats are only def. host; any mammal (even cats) can be intermediate host and only pathogenic in IH.

Back 41

Toxoplasma gondii

Front 42

Congenitally infected pups may exhibit CNS signs, hind limb paralysis. Hyperextension of the hind limbs. What parasite?

Back 42

Neonates with NEOSPORA infection may show CNS signs described here.

Front 43

Are horses definitive host for Sarcocystis?

Back 43

No, The horse is dead-end (aberrant) host.

Front 44

Zoonotic apicomplexa?

Back 44

Toxoplasma (cats are true definitive host), Sarcocystis, Cryptosporidium Parvum

Front 45

Horse Muscle

Back 45

Sarcocystis

Front 46

Poultry Feces

Back 46

Eimeria

Front 47

Ruminant Feces

Back 47

Eimeria

Front 48

What species SARCOCYSTIS has opossum as definitive host?

Back 48

S. neurona

Front 49

What are intermediate host for S. neurona? (6)

Back 49

many IH: armadillo, skunk, raccoon, sea otter, cat,

horse & marine mammals! serves as a dead end host (not true IH)

Front 50

Worldwide Distribution
Obligatory 2 host / Predator-Prey Life Cycle (canine & feline)
Regional Prevalences:
High in ruminants, swine & horses

Back 50

SARCOCYSTIS
* Predator-Prey Life Cycle

Front 51

SARCOCYSTIS can cause what in horse?

Back 51

Equine Protozoal Myeloencephalitis (EPM)
# 1 Cause of neurological signs in horses.

Front 52

T or F: S. neurona is of much importance in equine pathology

Back 52

True: horse is not true intermediate, b/c dead end host

Front 53

More than 60% cases of Equine Protozoal Myeloencephalitis (EPM) (sarcocystis) seen in what age group?

Back 53

60% of the cases are in > 4-yr-olds
but ages range from 2 mo → 19 yr-old

Front 54

Definitive host for Sarco. cruzi

Intermediate host for "

Back 54

canine, coyote, red fox, raccoon, wolf
~IH is cattlecattle

Front 55

(EPM) (sarcocystis) seen mostly in what horse breeds? (3)

Back 55

Thoroughbreds, Standardbreds, and Quarter Horses affected most often.

Front 56

How does predator become infected with Sarcocystis ?

Back 56

predator becomes infected when ingest "sarcocyst" in muscle (cardiac or sk.) tisssue of prey (IH)

Front 57

Asexual phase of Sarcocystis is in DH or IH?

Back 57

intermediate host
(in muscle sarcocyst have brady zoites = slowly diving merozoites)

Front 58

Species of sarcocystis which has human as DH? What are IH?

Back 58

sarcocystis hominis (IH is cattle)
sarco.suihominis (IH is pig)

Front 59

Definitive host for Sarco. cruzi, S.equicanis, S.tenella, S.fayeri, S.miescheriana?

Back 59

canine, coyote, red fox, raccoon, wolf

Front 60

What is IH for S. tenella (in wild dogs, raccon)?

Back 60

S. tenella IH is sheep
~DH in wild dogs, raccon

Front 61

Most specific and sensitive test for DIAGNOSIS: EPM? (2)
(Equine Protozoal Myeloencephalitis )

Back 61

Western blot (and IFAT) to detect anti-S. neurona antibodies in CSF (NOT serum), because guess specific aB can cross BBB?

Front 62

Differential Diagnosis of EPM (7)

Back 62

Neospora
Toxoplasma
Sarcocystis spp.
Equine Herpes
Head or spine trauma
Cervical stenotic myelopathy
Wobbler’s syndrome

Front 63

Symptoms of EPM

Back 63

Variable; asymmetric posterior ataxia, weakness, proprioceptive deficits, muscle atrophy and a wide variety of cranial nerve signs. Severity is directly related to the number of sporocysts ingested.

Front 64

Very sensitive and specific for the detection of S. neurona antigen in histopathology prepared tissue samples (e.g., brain and spinal cord)?

Back 64

Avidin-Biotin Immunohistochemical Staining (immunohistochemisty)

Front 65

3 ways cats can contract Toxoplasma?
Which leads to shortest PPP?

Back 65

ingest cyst, oocyst, or tachyzoite

*PPP is 3-10 days for TISSUE CYST -induced infections (occurs in 97% of cats that ingest tissue cysts). Ingesting sporulated T. gondii oocysts or tachyzoites results in oocyst-excreting infection in only 16-20% of cats.

Front 66

TOXOPLASMA gondii - DH ?

Does sexual or asexual reprod. occur in cat?

Back 66

CAT

BOTH SEXUAL & ASEXUAL REPRODUCTION = OOCYSTS IN THE FECES

Front 67

Sexual development: in cat takes place in what tissue?

Asexual development?

Back 67

Sex. dev. : occurs in intestinal epithelium

Asexual development: Intestinal phase (Merozoites).

Front 68

What is Extraintestinal phase of toxoplasma?

Back 68

Extraintestinal phase - Tachyzoites are rapidly-dividing tissue stages. Usually found in the liver, lungs, spleen, or lymph nodes.

Front 69

T or F:Toxoplasma tachyzoites can cross the placental barrier (transplacental transmission).

Back 69

true

Front 70

Toxoplasma Bradyzoites (in cysts) are the slowly dividing tissue stages that are usually found in the ?? (tissues)

Back 70

Bradyzoites (in cysts) are the slowly dividing tissue stages that are usually found in the brain, heart, skeletal muscle and eye.

Front 71

Facultative intermediate hosts: for toxoplasma?

Back 71

Facultative intermediate hosts: Wide range of vertebrates/birds.

Front 72

Infective Stages for toxoplasma?

Back 72

Sporulated oocysts (10 µm) – only domestic and wild felids shed oocysts

Front 73

Symptoms of toxoplasma in human infections ?

Back 73

Most human infections are ASYMPTOMATIC; but can have acquired and re-activated toxoplasmosis
---
if immunocompr. Fever, malaise, lymphadenopathy, encephalitis, myocarditis, pneumonitis and retinochoroiditis.

Front 74

Congenital toxoplasmosis leads to ? (5)

Back 74

Retinochoroiditis, intra-cerebral calcification, hydrocephalus, convulsions and death.

Front 75

Immunity to toxoplasmosis?

Back 75

Intestinal immunity is NOT life long.
Immunosuppression with high doses of corticosteroids will cause chronically infected cats to re-excrete T. gondii oocysts.

Front 76

Cats that have previously recovered from a T. gondii infection will re-excrete T. gondii oocysts if they get a primary ____.

Back 76

I. felis infection

Front 77

T or F: Cats that have I. felis followed by T. gondii inf. will re-excrete T. gondii oocysts if challenged with I felis.

Back 77

False; dev. strong immunity to T. gondii NOT re-excrete it if have I.felis first!

Front 78

Toxoplasmosis in cattle? sheep?

Back 78

RARE; ; usually asymptomatic in cattle

Major cause of abortion; focal placentitis. in sheep

Front 79

A sheep has aborted due Toxoplasma inf.; could you do fecal float to diagnose?

Back 79

NO, only in cat!