parasitology intro and nematodes

Question 1

which categories of helminths require an intermediate host

Answer 1

cestodes and some trematodes

Question 2

list 7 ways parasites cause harm to hosts

Answer 2

• suck blood
• feed on solid tissues
• compete with host for the food is has digested
• cause mechanical obstructions
• reduce host’s resistance
• destroy host cells
• carry diseases

Question 3

list 8 ways to control an animal’s exposure to parasites

Answer 3

• worm all animals at same time
• remove fecal material
• rotate pastures
• don’t place feed on the ground
• control intermediate hosts
• isolate new animals
• keep young animals in separate quarters
• change bedding

Question 4

2 reasons it is useful for VTs to know about parasite life cycles

Answer 4

so they can treat and prevent parasites

Question 5

list 5 effects ascarids can have in young animals

Answer 5

• lack of growth
• pot-bellied
• pass adult worms in feces
• dull hair coat
• damage to lungs

Question 6

visceral larva migrans

Answer 6

syndrome caused by ascarid larvae migration in an abnormal host

Question 7

3 ways a canine or feline can get roundworm

Answer 7

• ingestion
• skin penetration of infective larvae
• ingestion of intermediate host
  (Fecal-oral, transplacental, transmammary)

Question 8

4 ways an animal may be infected with hookworm

Answer 8

• ingestion
• larvae pass through placenta
• transmammary
• larvae may penetrate skin
  (Ingestion, transplacental, transmammary, larvae penetrate skin)

Question 9

which nematode parasite causes anemia

Answer 9

hookworm

Question 10

cutaneous larval migrans? what causes it? another name?

Answer 10

intensely pruritic eruption of human skin; caused by migration of nematode larvae; “creeping eruptions”

Question 11

how do horses become infected with stronglyes

Answer 11

ingestion

Question 12

the small strongyle adults live in what part of the horse

Answer 12

cecum

Question 13

list 3 effects strongyles have on the host

Answer 13

• damage to mesenteric arteries
• damage to liver
• anemia

Question 14

what horse parasite is becoming resistant to worming medications

Answer 14

small strongyles

Question 15

what types of animals are susceptible to trichostrongyles? how do they get infected?

Answer 15

ruminants by ingestion

Question 16

what parasite ova is similar in appearance to that of whipworm

Answer 16

capillaria

Question 17

4 animals that get lungworms

Answer 17

sheep, goats, cattle, and pigs

Question 18

adult lungworms live in the bronchi or lungs. what life-stage do we look for to diagnose lungworms in ruminants? what fecal test is done?

Answer 18

larvae; baerman technique

Question 19

what are symptoms of pinworm infection? what is the most common domestic species to get them? can people get them from an animal? can a cow get them from a horse?

Answer 19

tail rubbing, pruritus in anal glands, broken hair; horses; pinworms are host specific

Question 20

pinworm ova

Answer 20

elongated, oval, and flat on one long side

Question 21

what is a way to diagnose pinworm infection other than fecal flotation

Answer 21

scotch tape test

Question 22

capillaria plica is the canine bladder worm. how do the eggs get in the feces?

Answer 22

coughed up and swallowed and shed in feces

Question 23

3 ways that capillaria ova differ from trichuris ova

Answer 23

• off center plugs
• smaller
• lighter shade of yellow
• more barrel shaped

Question 24

endoparasite

Answer 24

parasite live within the body

Question 25

ectoparasite

Answer 25

parasite lives on the outside of the body

Question 26

pseudoparasite

Answer 26

object mistaken for a parasite

Question 27

host

Answer 27

organism that harbors a parasite

Question 28

definitive host

Answer 28

harbors the adult parasite

Question 29

intermediate host

Answer 29

harbors the larval form

Question 30

direct lifestyle

Answer 30

no intermediate host

Question 31

indirect lifestyle

Answer 31

intermediate host involved

Question 32

free living

Answer 32

a stage that lives in the environment

Question 33

host specific

Answer 33

the parasite only lives in one or few related host species (eimeria)

Question 34

Pre-patent period

Answer 34

time from initial infection until the parasite matures and reproduces

Question 35

Fecal-oral

Answer 35

common means of transmission for parasites with direct lifecycle

Question 36

Infective

Answer 36

ova or larva can mature if they get into the definitive host

Question 37

Embryonated

Answer 37

Larva visible inside the ova

Question 38

not a nematode

Answer 38

tapeworm