Nematodes Large Animal

Question 1

Which nematodes effect the GI system in large animals?

Answer 1

Trichostrongyles spp
Oxyuris equi
Trichinella spiralis

Question 2

Which nematodes effect the circulatory system in large animals?

Answer 2

Strongylus viulgaris

Question 3

Which nematodes effect the respiratory system in large animals?

Answer 3

Dictyocaulus spp

Question 4

Which nematodes effect the integumentary system in large animals?

Answer 4

Onchocerca cervicalis

Question 5

What are the hosts for Trichostrongyles?

Answer 5

Cattle, sheep, goats

Question 6

Where in the body does Trichostrongyles effect?

Answer 6

Abomasum in cattle
Large & small intestine

Question 7

How do you diagnose Trichostrongyles?

Answer 7

Fecal float for eggs
Fecal culture for larval identification

Question 8

What is the lifecycle of Trichostrongyles?

Answer 8

Eggs are passed in feces and hatch into free living larva. Matures to 3rd stage where it becomes infective. Climbs onto grass and is ingested when animal is eating grass. Matures to adult in intestines

Question 9

What are the clinical symptoms of Trichostrongyles?

Answer 9

Bottle jaw, anemia, weakness, diarrhea, sudden death

Question 10

Which nematode is known as the”equine pinworm”?

Answer 10

Oxyuris equi

Question 11

Where in the body does Oxyuris equi effect and what does it cause?

Answer 11

Lives in cecum, colon, & rectum. Causes pruritis (horse scratching rear end) and tail hairs being broken

Question 12

How can you identify Oxyuris equi?

Answer 12

Tape impressions, anal scraping, fecal floatation

Question 13

T/F only female pinworms can deposit eggs on horses

Answer 13

True. Only female pinworms can deposit eggs on the anus

Question 14

What are the hosts of Trichinella spiralis?

Answer 14

Definitive & intermediate: pig
Abberant: humans

Question 15

Where is the body does Trichinella spiralis effect?

Answer 15

Definitive host in the small intestine
Muscle tissue in the intermediate host

Question 16

How do you diagnose Trichinella spiralis?

Answer 16

Eggs and larva are seldom recovered. Muscle biopsy or serology

Question 17

What are the clinical signs of Trichinella spiralis?

Answer 17

Sometimes asymptomatic
Muscle damage

Question 18

What is the lifecycle of Trichinella spiralis?

Answer 18

Females give live birth (viviparous). Larva penetrate mucosa and enter blood, then enter skeletal muscle where they encyst. Able to stay alive while encysted for long periods of time, then they die and calcify. If they don’t die they become infective larva. Meat is ingested and larva enters epithelial cells

Question 19

What is the zoonotic potential of Trichinella spiralis?

Answer 19

Undercooked pork or wild game

Question 20

What is the circulatory nematode in large animals?

Answer 20

Strongylus vulgaris

Question 21

Where is Strongylus vulgaris located in the body?

Answer 21

Blood vessels of the large intestine. Migrate to cranial mesenteric artery

Question 22

What are the clinical symptoms of Strongylus vulgaris?

Answer 22

They cut off blood supply to the intestines. Weight loss, colic, poor appetite, lethargy

Question 23

How do you diagnose Strongylus vulgaris?

Answer 23

Fecal floatation

Question 24

What is the lifecycle of Strongylus vulgaris?

Answer 24

Adults in large intestine lay eggs. Eggs are passed in feces and develop into L3 infective larva on the grass. Larva stay in water drops and are suspended on grass, horse eats grass and ingests larva. Larva enters large intestine and mature to L4. Then penetrate mucosa and enter blood vessels. Mature to L5 before penetrating small intestine

Question 25

What is the prepatent period of Strongylus vulgaris?

Answer 25

6-7 months

Question 26

Which is the respiratory nematode in large animals and which animal does it effect?

Answer 26

Dictyocaulus arnfieldi. Effects equines

Question 27

Where is Dictyocaulus arnfieldi in the body and what does it cause?

Answer 27

Bronchi & bronchioles. Causes persistent cough, airway obstruction, & increased respiratory rate

Question 28

What is the diagnosis of Dictyocaulus arnfieldi?

Answer 28

Fecal floatation for eggs & larva

Question 29

What is the lifecycle of Dictyocaulus arnfieldi?

Answer 29

Embryontated egg/larva is passed. Mature to infective L3 on grass where it is ingested by equine. Migrates from GI to the lungs where is matures to adults in the bronchi

Question 30

What is the prepatent period of Dictyocaulus arnfieldi?

Answer 30

2-3 months

Question 31

Which is called the integumentary nematode and which animal does it effect?

Answer 31

Onchocerca cervicalis. Horses

Question 32

Which nematodes is the equine filarial worm?

Answer 32

Onchocerca cervicalis

Question 33

Where does Onchocerca cervicalis effect?

Answer 33

Nuchal ligament in adults & microfilaria in the dermis

Question 34

What are the hosts of Onchocerca cervicalis?

Answer 34

Definitive: horse Intermediate: midges (flies)

Question 35

What are the clinical signs of Onchocerca cervicalis?

Answer 35

Cutaneous: alopecia, scales, pruritis Opthalmic: "moon blindness" blue cornea

Question 36

How do you diagnose Onchocerca cervicalis?

Answer 36

Skin biopsy with saline prep