Dictyocaulus arnfieldi (1)

Question 1

What are the hosts?

Answer 1

Donkeys

 - Adapted
 - Few to no clinical signs
 - Animals of all ages
 - Egg with L1 or L1

Horses

 - Rarely reaches sexual maturity - Foals and yearlings exceptions
 - Damage to pulmonary tissue
 - Chronic cough
 - Bronchial alveolar lavage
 - In endemic areas do not pasture horses and donkeys together

Question 2

Describe an adult

Answer 2

Long, slender, white

3-8 micro m

In the bronchi and trachea

Question 3

Describe the larvae

Answer 3

L1 recovered from feces

400-500 micro m

Bronchoalveolar lavage can be used to recover eggs and larvae

Question 4

Describe the life cycle

Answer 4

Direct

L1 are found in feces instead of egg

L3 is infective

L3 migrates through intestinal wall via lymph and blood -> lungs

Mature in trachea and bronchi

Question 5

What is the site of infection?

Answer 5

Bronchi and trachea

Question 6

Describe the Pathogenesis

Answer 6

Non-pathogenic in donkeys - All ages, few clinical signs, adapted

Pathogenic in horses (foals/yearlings) where the life cycle normally does not reach patency

 - Penetration
        - Larval migration
        - No clinical signs
 - Patent
        - Larvae develops to adults in lungs
        - Alveolitis and bronchi

Question 7

Describe the clinical signs

Answer 7

Prepatent phase alveolitis followed by bronchitis

Bronchitis

Pneumonia - result of aspirated eggs/L1

Edema and Emphysema

Alveolar epithelialization of entire lung lobes

Frequent bouts of coughing at rest

Squeaks and crackles over posterior lung lobes

“Air hunger” position of mouth breathing with head/neck outstretched

Damaged to pulmonary tissue

Question 8

How do you diagnose?

Answer 8

Clinical signs

History

Endemic area

Identification of L1

Necropsy

Question 9

How do you treat and prevent?

Answer 9

Anthelmintics

Avoid posturing horses and donkeys together in endemic areas

Management

Question 10

What is the common name?

Answer 10

Lungworm