Parasitology 5: Ascaridida

Question 1

Main characteristics Ascaridida nematoda

Answer 1

Big
Robust
GI tract

Question 2

Lay term name for Ascaridida

Answer 2

Roundworms

Question 3

Significance of size for Ascaridida

Answer 3

• Biggest nematodes
• Between 5 - 40 cm

Question 4

Type life cycle for Ascaridida

Answer 4

Direct

Question 5

Where do Ascaridida live and what do they feed on?

Answer 5

• Live in lumen (unattached)
• Feed on lumen contents, host fluids

Question 6

Characteristics of Ascaridida egss

Answer 6

LIVE UP TO 10 YEARS
- Unembryonated
- Thick shell
- High resistant to environmental conditions

Question 7

When is Ascaridida infective stage?

Answer 7

(Egg with L3)
- Embryonated egg
- The infective larva will not hatch until egg is swallowed by the host.

Question 8

How to diagnose Ascaridida?

Answer 8

• Eggs in feces
• patent infections are easy to diagnose

Question 9

What is this, what is specific about it?

Answer 9

Ascaridida egg
- thick, rough shelled

Question 10

Ascaridida mammalliam species?

Answer 10

Parascaris spp.
Toxocara spp.

Question 11

Parascaris spp Ascaridida infects what animal?

Answer 11

Horses

Question 12

Lifecycle of Parascaris?

Answer 12

• Eggs passed in manure
• Larvae hatch in intestine, penetrate lumen wall
• Hepatotracheal migration: Carried to liver in blood - Enter hepatic portal system - Reach lungs 1 wk after infection - Coughed up and swallowed - Return to small intestine
• Prepatent period ~3 months

Question 13

Parascaris clinical important?

Answer 13

• Young horses
• Low worm numbers can be subclinical
• Adults in small intestine
• Larvae in lungs

Question 14

What is the clinical significance of parascaris adults in small intestine?

Answer 14

• Compete with host for nutrients
• Poor condition
• Rough hair coat
• Pot bell
• Very heavy infection can lead to obstruction or perforation of impaction of GIT

Question 15

What is the clinical significance of parascaris Ascaridida in the lungs?

Answer 15

• Mechanical and inflammatory damage
• Nasal discharge

Question 16

What is the immunity trends of parascaris?

Answer 16

• Immunity develops well so adults rarely have patent infections
• Adults do not ply a role in parasite transmission
• Occurs in young horses (<2-3 years)

Question 17

What breed is Toxocara canis and cati in?

Answer 17

Dogs and cat

Question 18

Special characteristics of toxocara cati?

Answer 18

Narrow head with wing shaped.
Pathognomic of this nematode.

Question 19

Toxacara canis survival in environment?

Answer 19

• Eggs passed in feces
• takes 3-4 weeks in the environment to become infective
• can survive in environment fo r2-3 years

Question 20

life cycle of toxocara canis

Answer 20

Question 21

Routes of transmission for Toxocara canis?

Answer 21

• Ingestion of infective eggs
• Transplacental**
• Transmammary infection
• Paratenic hosts

Question 22

Toxocara canis clin signs in severe cases

Answer 22

• Diarrhea
• Colic
• pot belly
• Vomiting (worms can be seen)
• Poor hair coat
• Intestinal obstruction
• pneumonia

Question 23

How to diagnose Toxocara caninia?

Answer 23

• Patent infectionsL fecal exam
• Somatic survivors

Question 24

What are the big 3 nematodes?

Answer 24

Hookworms
Roundworms
Whipworms

Question 25

Toxocara cati significance?

Answer 25

• Somatic reservoir is less important than canis
• Some transmammary seems to be less important
• longer PPP

Question 26

Swine Ascaridida?

Answer 26

• Zootonitc
• Ascaris suum

Question 27

Racoon Ascaridida?

Answer 27

• Zoonotic
• Baylisascaris procyonis

Question 28

Humans Ascaridida?

Answer 28

Ascaris lumbricoides

Question 29

Cattle Ascaridida?

Answer 29

Toxocara vitulorum