Exam II - Stomach Nematodes

Question 1

What is/are the host(s) for Draschia megastoma & Habronema spp?

Answer 1

All equids

Question 2

Describe the appearance of Draschia megastoma adults

Answer 2

Adults are 133 mm long, have a funnel-shaped buccal cavity and form nodules close to the margo plicatus

Question 3

Describe the appearance of Habronema spp adults

Answer 3

Habronema spp adults are longer than D. megastoma (22-25 mm) with cylindrical buccal cavities

Question 4

Describe the appearance of the egg for Draschia megastoma & Habronema spp

Answer 4

thin-shelled, larvated and 40-55 x 6-16 um

Question 5

List some intermediate hosts for Draschia megastoma & Habronema spp

Answer 5

• Diptera: Muscidae
• Musca spp.
• Stomoxys calcitrans

Question 6

What is/are the site(s) of infection for Draschia megastoma & Habronema spp?

Answer 6

Adults & Larvae in stomach. L₃ in skin

Question 7

Describe some pathogenesis associated with Draschia megastoma & Habronema spp

Answer 7

Larvae: cutaneous habronemiasis & cutaneous draschiasis, ulceration, granular conjunctivitis, nodules in the lungs

Adults: gastritis, nodules or tumors

Question 8

What are some clinical signs seen with Draschia megastoma & Habronema spp?

Answer 8

Larvae: “summer sores” (cutaneous habronemiasis)

Adults: gastritis

Question 9

How would you diagnose Draschia megastoma & Habronema spp?

Answer 9

Larvae: cutaneous lesions (summer sores). Larvae can be found with biopsy or scrapings of lesions

Adults: fecal flotation

Question 10

Describe the treatment & prevention options for Draschia megastoma & Habronema spp

Answer 10

• MCLs
• Fly control
• ivermectin no longer effective… resistance perhaps?

Question 11

What is the infective stage for Draschia megastoma & Habronema spp?

Answer 11

L₃