Parasitology Test 2 2011

Front 1

What are the 3 phyla of helminths of veterinary importance?

Back 1

1. Platyhelminthes
2. Acanthocephala
3. Nemathelminthes (p.61)

Front 2

What is the common name of worms belonging to the class Nematomorpha?

Back 2

Hair worms or horse-hair worms
(p.61)

Front 3

What phylum and class do helminths belonging to the superfamily Gordioidea belong to?

Back 3

Phylum: Nemathelminthes
Class: Nematomorpha
Superfamily: Gordioidea
(p.61)

Front 4

What type of bodies to roundworms (intraphylum: nematoda) have?

Back 4

* Elongate cylindrical bodies with no segmentation
* Complete digestive tract (mouth to anus)
(p.61)

Front 5

Are roundworms (intraphylum: nematoda) dioecious or monoecious?

Back 5

Dioecious: separately sexed individuals
(p.61)

Front 6

Common name: Nematodes

Back 6

Rounds

Front 7

Common name:Cestoda

Back 7

Tapes

Front 8

Common name:Trematoda

Back 8

Flukes

Front 9

Common name: Acanthocephala

Back 9

Thorny headed

Front 10

Body type: Nematodes

Back 10

Cylindrical

Front 11

Body type: Cestoda

Back 11

Flat

Front 12

Body type: Trematoda

Back 12

Flat

Front 13

Body type: Acanthocephala

Back 13

Cylindrical

Front 14

What is the only helminth type thats segmented?

Back 14

Cestoda

Front 15

What are the only helminths type that have a mouth

Back 15

Nematodes and Trematodes

Front 16

What are the only helminths type that have a GI Tract

Back 16

Nematodes and Trematodes (blind tract)

Front 17

What is the only helminth type that has an anus/cloaca?

Back 17

Nematode

Front 18

What are the only helminths type that have a body cavity

Back 18

Nematodes and Acanthocephala

Front 19

What are the only helminths type that have an anterior sucker

Back 19

Cestode, Trematode, and Acanthocephala

Front 20

What intraphylum do the roundworms belong to

Back 20

Nematoda

Front 21

Body type: roundworms

Back 21

Elongate cylindrical bodies with no segmentation

Dioecious

Front 22

Do roundworms have a body cavity?

Back 22

yes

Front 23

GI tract: roundworms?

Back 23

Complete (mouth to anus)

Front 24

Life cycle: rounds?

Back 24

direct or indirect

Front 25

Which helminths have an idirect life cycle?

Back 25

* Nematoda (can be direct or indirect)
* Cestoda
* Trematoda
* Acanthocephala

Front 26

5 types of esophagus in rounds?

Back 26

1. Rhabditiform: anterior and posterior swelling, found in soil and plant nematodes, and pre-infective larval stages of several parasitic nematodes

2. Filaform: simple tube like structure

3. Club shapes: baseball bat

4. Bulbed: prominent bulb at posterior

5. Stichosome: stacked donuts

Front 27

Diff in anus in male/female rounds?

Back 27

Anus: females

Cloaca: Males

Front 28

Development of nematodes

Back 28

* Egg through 4 larval stages to adult

L1: hatches and feeds on fecal material molts to L2 then L3

* L3 retains the cuticle of L2 for protection

* L3 is the usual Infective stage

Front 29

Nematodes: on/off host?

Back 29

Egg-Molt L3 in environment or IH

L3-Adult cause infection in Dh

Front 30

6 migration types of nematodes

Back 30

1. Local migration (usually within gut and all paratitic stages found in same organ)

2. Hapatotracheal migration (gut through vasculature to trachea back to gut)

3. Lymphatic tracheal migration (gut through lymphatics to trachea back to gut)

4. Skin tracheal migration (Skin to trachea to gut)

5. Somatic (hepatic aortic, lymphatic aortic, skin aortic)

6. Direct tissue migration (direct penetration theough organs)

Front 31

Characteristics of neatodes belonging to the superfamily Rhabditoidea

Back 31

* Only females are parasitic

* direct life cycle

* one of the 1st parasites occuring in young animals

* thin shelled larvated eggs or larvae oassed in feces

Front 32

nematode of importance belonging to the superfamily Rhabditoidea

Back 32

* Strongyloides stercoalis
(intestinal threadworm)

Front 33

Hosts and zoonicity: Strongyloides stercoalis

Back 33

Small intestine of man, primates, and dogs
Possibly zoonotic

Front 34

Infective Stage: Strongyloides stercoalis

Back 34

L3

Front 35

Life cycle: Strongyloides stercoalis

Back 35

DIRECT LIFE CYCLE
L1: passed in feces
L3: two options: either become infective filiform larvae which penetrate the skin OR become free living adults, which sexually reproduce

* Susceptible host: L3 undergo cutaneous tracheal migr, molt in lungs, coughed up and swallowed, where they mature in small intestine; female burrow into mucosa and produce larvated eggs, which may hatch and burrow into the mucosa, carried to the lungs, and repeat the cycle in autoinfection (watery diarrhea, abdominal distension)

* Resistant host: L3 enter older host w/stronger immunity, undergo skin aortic migration (bypass the lungs), and enter various tissues including mammary gland; mobilized/transferred during first few weeks of lactation

* Transmammary transmission: major method of trans to pups; do not undergo further migration, but establish in small intestine

Front 36

Sci. name for the hookworm?

Back 36

Ancylostoma caninum

Front 37

What super family does Ancylostoma caninum (hookworm) belong to

Back 37

Stongyloidea

Front 38

Chaacteristics of superfamily: Stongyloidea

Back 38

* Found in intestines, resp. tract or kidney fat

* Direct life cycle

* Well developed buccal cavity and muscular culb shaped esophagus

* females pass thin shelled segmented eggs

Front 39

2 families of the superfamily Stongyloidea

Back 39

1. Ancystomidae

2. Strongylidae

Front 40

Method of penetration of hookworms (Ancylostoma caninum)

Back 40

SKin penetration

Front 41

Hosts and zoonicity

Back 41

Small intestine of dogs/canids
Cutaneous Larval Migrans

Front 42

Life cyle: hookworms (Ancylostoma caninum)

Back 42

DIRECT
Segmented oval eggs passed in feces

Susceptible host: L3 undergo skin tracheal migration

Resistant host: skin-aortic migration; with L3 becoming hypobiotic in somatic tissues (mammary glands, etc)

Front 43

Egg type: hookworms (Ancylostoma caninum)

Back 43

Segmented oval eggs

Front 44

Phyla and Infraphylum: (Ancylostoma caninum)

Back 44

Phyla: Nemathelminthes

Infraphylum: Nematoda

Front 45

Characteristics of the family Strongylidae

Back 45

* Found in L. intestine or renal fat

* Large mouth surrounded by leaf crown

* Plug or blood feeders

* Direct life cycle

Front 46

What are Cyathostomes?

Back 46

Callective name fiven to 6 genera and approx. 36 species strongylate worms in the large intestine of equids

Phyla: Nemathelminthes

Infraphylum: Nematoda

Family: Strongylidae

Front 47

Common name: Cyathostomes?

Back 47

Blood worms, small strongyles

Front 48

Cyathostome of importance

Back 48

Strongyloidea
Stongylidae

Front 49

Hosts and zoonicity: Strongyloidea
Stongylidae

Back 49

Large intestine of horse

Front 50

Infective stage: Strongyloidea
Stongylidae

Back 50

L3

Front 51

Life cycyle; Strongyloidea
Stongylidae

Back 51

DIRECT, Mucosal migration

Segmented eggs passed in feces;

L1 feed on feces and develop to L3

L3 stay in pasture 1w-1m, but can survive for 8m and get consumed when horse is grazing;

L3 enter mucosa of LI and molt to L4;

Some larvae arrest development in mucosa (L3, L4) – hypobiosis;
Number of larvae returning to lumen depends on season and population of adults (L3/L4 will overwinter in mucosa layer; removal of adults stimulates activity)

L5 remain in LI to breed and feed on blood/mucosa

Front 52

Cyathostomiosis syndrome

Back 52

1-4yr horse, late winter/early spring, after deworming, loosing body condition, non-febrile, diarrhea;
Larvae acquired in one grazing season become adults the next season