Exam II - Dictyocaulus arnfieldi

Question 1

What is the common name for Dictyocaulus arnfieldi?

Answer 1

Lungworm

Question 2

What is/are the host(s) for Dictyocaulus arnfieldi?

Answer 2

Donkeys. In horses, adults usually don’t reach sexually maturity.

Score 1 for donkeys

Question 3

Which life cycle stages of Dictyocaulus arnfieldi are recovered in feces and bronchial washings?

Answer 3

L₁ (400 um long) and eggs (75 um long)

Question 4

Describe the appearance of Dictyocaulus arnfieldi adults

Answer 4

Long white nematodes (8 cm) in lungs

Question 5

Describe the Dictyocaulus arnfieldi life cycle

Answer 5

Direct. Adult stages in bronchi lay eggs containing L₁.

Eggs hatch in lungs and in feces (eggs & L₁ are found in feces)

Develop to L₃, migrate from feces to herbage where ingested

PPP is 2-4 months

Question 6

Describe any pathogenesis and clinical signs associated with Dictyocaulus arnfieldi in horses and donkeys

Answer 6

Horses: damage to pulmonary tissue, chronic, productive cough

Donkeys: no clinical signs

Question 7

How would you diagnose Dictyocaulus arnfieldi?

Answer 7

L₁ recovered in fresh feces and lung washings

Adults in lungs at necropsy

Question 8

What are some treatment & prevention options for Dictyocaulus arnfieldi?

Answer 8

In endemic areas, don’t pasture horses & donkeys together

Question 9

What is the infective stage of Dictyocaulus arnfieldi?

Answer 9

L₃